Fear Factory and Iron Maiden.... how can you go wrong =]

Juzari:
Carmagedon 1 and 2, it just fits perfectly

Fear Factory and Iron Maiden... how can you go wrong =D

Portal most definately Still Alive is an instant classic.

danosaurus:

Vigormortis:
Most of my favorites have been listed and I'm pretty sure this thread's been done numerous times before, but what the hell, here we go:

Pretty much everything by Rare - again, just catchy tunes I find myself still humming on occasion to this very day

Yep, they were always 1 step above nintendo in the music composing i reckon, Banjo-Kazooie had an amazing soundtrack and was (I think) one of the first games to implement that whole environment-change = music-change thing, like how the theme song would be playing as you're walking around Gruntildas' Lair and it would morph into a Xmas-esque version of the song with bells and such when you approached the entrance of the snow level and so on =]

I'm not sure it was the first, but it was (and still is) one of the most well implemented cases of that kind of music transition.

GothmogII:
Arcanum for sure, Ben Houge was great, it's done mostly in string quartet, a pleasure to listen to. I've got several tracks on my MP3, Sierra were nice enough to upload em to their site,
http://www.terra-arcanum.com/sierra/media/media-soundtrack.html

Homeworld had a pretty good soundtrack too, although Agnus Dei sticks out as something memorable.

Oh wow, thanks for the link. I may have to dust off my violin and have a go at some of those. Also, yes, Homeworld has a great soundtrack to it.

Most great games have a great soundtrack to them, it would be hard to call them "great" games if they didn't. As such I don't feel it would be fair to list a number of games that stand out for me because I'd be sure to forget loads of equally great ones.

There is, however, one piece of music from one game in particular that I would have to say is my all time favourite.

"Baba Yetu" from CIV4

You can hear it on the composer's site:
http://christophertin.com/samples.html

Even though the game contains dozens of tunes from great classical composers like Bach, Beethoven, Mozart, etc.. I always just set it up to play Baba Yetu on a continuous loop when I play the game. Not only is it an absolutely perfect soundtrack for the game it's also just a fantastic piece of music in it's own right.

There are a lot of games I like a lot more than CIV4 which also have truly excellent sound tracks but I'd be a lying fangirl if I tried to claim their soundtracks were better.

Some people may hate me for saying this but I LOVED the music in Quake 2 :P It was all done by Nine Inch Nails was it not? Anyways, its actually one of the factors that got me into metal music.

RedSigma:
Some people may hate me for saying this but I LOVED the music in Quake 2 :P It was all done by Nine Inch Nails was it not? Anyways, its actually one of the factors that got me into metal music.

Hmmm i believe Trent Reznor (NIN) had a hand in developing sounds//ambience//music in the first Quake.
Quake 2 however was all by 'Sonic Mayhem', a German Producer who produces music and sound effects for a number of mainstream games, very talented man!

Quake Arena was done by Frontline Assembly and i can't remember the other artists name, but if your'e into Industrial//Metal and haven't checked out Frontline assembly, it's worth your time.
It's 2 guys, one was the keyboardist//Synth from 'Fear Factory' and the other dude is responsible for the dance group 'Delerium'. Very interesting combination of talents that have produced some amazing works =]

Mass Effect. That one's my favorite, I think.

Nquoid:
Terry Taylor's soundtrack for the Neverhood. Whilst not like a normal video game soundtrack, the tunes perfectly reflect the game. Also some of the songs are IMPOSSIBLE to sing along to and will definately bring a smile to your face.

Anybody remember the Bonus Level song in Skull Monkeys? Hilarious

Mechcommander and Total Annihilation both had good fightin' music that would slow down when the action died off. I also like the music in Final Fantasy, tho the songs seem to be pretty simmilar from game to game.

Anything with piano music is also fine by me (the Seige of Madrigal secret in Halo is perfect).

EDIT: How could I forget Metroid?

TheMadDoctorsCat:
Anybody remember how good the old C64 game soundtracks could be? Nope? Just me then...

my phone ringtone is the standard ocean loader theme so yeah, some still actively listen to c64 and amiga soundtracks :)

my c64 favourites probably being skate or die, delta (even though it totally aped koyaanisqatsi) armalyte, wizball, parallax, LN, LN2 & PLATOON!!

i still wonder what those composers are up to these days, especially martin walker

my vote for best soundtrack goes to vagrant story, hitoshi sakimoto who also worked on ffxii composed some really great tracks for that game. also gotta love ffviii.

kudos to jesper kyd for his works with & without the hungarian radio choir (shame about the movie though :(

sakuraba for making dungeon rpg's seem less so (the original versions not so big a fan of the retail arranges)

:already mentioned:
Mega man 2, Ocarina of Time, Actraiser, Axelay, Super Metroid, Metroid Prime, Super Castlevania 4, Castlevania: SotN. and Chrono Trigger - fantastic works, schala's theme still slows my heartbeat & relaxes me. not forgetting assault suit valken.

anybody who like me is a fan of the silent hill music really should see the film, a great example (maybe the first) of video game music making it to the big screen & really doing the film a favour.

a lot of mentions for HL2 & Halo, i'm a little surprised but hey :)

Nobody's mentioned Ikaruga yet?!? I'm not saying the others here aren't worthy mentions, but, it's so epic...

I like Bioshock, simply because you get this lovely ambient music, and then somewhere in the background you hear these wonderful strains of some fantastic, cheeful thirties or forties hit while you're being cheerfully attacked by some Splicer.

For music that seems to instantly alter my mood, and make even the worst day into something wonderful for me, I'd have to say the Okami soundtrack. Especially the Shinshuu Plains one. I dare anyone to listen to the soundtrack and not find one song that makes them happy.

I really like the music in Halo 2 that couples with the action scenes. It really puts you at the edgo of your seat.

Mafia - music by Django Reinhardt!
Battlefield: Vietnam - obviously inspired by Vietnam movies, still a nice selection
Grim Fandango - dance companeros!
HoMM 3/5 - perfect fantasy music
Wing Commander - classic space opera music

ah, the list goes ever on and on, I probably missed a lot...

http://www.ocremix.org/

Most everything on my MP3 player is from this site.

TheBenMan and Nquoid speak the truth. The Neverhood and Skullmonkeys has some of the best music I have ever heard in a video game. Their offbeat scores defy genres and conventional themes, but they fit perfectly with the wacky claymation settings.

I also enjoy the soundtracks from the following games:
Super Smash Bros. Brawl (the memories those remixes evoke!)
Viewtiful Joe 1 and 2
Donkey Kong Country 1 and 2
Metroid Prime
Halo
Medal of Honor: Frontline

Yoko Shimomura's and Noriko Matsueda's score for the first Front Mission was epic. Infinitely better than any Final Fantasy score. Take that, Uematsu-san. The only good thing you ever did was Dancing Mad, Sephiroth fanboys be damned.

Star Wars: Republic Commando had an excellent score too, plus it was largely original work, which is pretty rare in a Star Wars game.

Oh yeah, Audiosurf. Best soundtrack ever.

Final Fantasy Tactics

OnlySniperLeft:
Portal most definately Still Alive is an instant classic.

People will be surprised at me for saying this, but my favorite song from Portal is actually much earlier in the game. From the game content files, you can see it's called "Self Esteem Fund". It was a very somber melody that got across the feeling of loneliness and fear in Chell, and a little sense of "Am I going to make it out of here?"

http://www.frankklepacki.com/

Go to the music player at the bottom and click on 'CnC series'.

Oh God. You got me started. I'm a huge, HUGE fan of videogame music.

I'm discounting any of these votes for games that have licensed tracks in their soundtrack. As a lover of original game music compositions, I find the use of licensed tracks almost offensive when you hear the creative, original soundtracks to games such as Symphony of the Night, Rez and Mario 64.
For me, a videogame soundtrack actually has to work in tandem with the gameplay and remain consistent, and that's why I'm absolutely shocked to see nobody mention Hideki Naganuma's work on Jet Set Radio and Sonic Rush. Sure, JSR did have some licensed tracks, but Naganuma's original compositions compliment those games so beautifully, perfectly and artistically that I'd refuse to play the games without them.
Similarly, every game in the Metroid series has used music that's nothing short of appropriate, wonderous and epic. Later Castlevania games have also proved to have awesome soundtracks - the colisseum in SOTN providing a memorable, funky break from the dramatic or melancholic scores that otherwise layer the game.
Does anybody remember the "Lorenzo's Soil" stage of Earthworm Jim 2? The music to that was so inconsistent in tone to the rest of the game, yet actually worked for that level better than any other song in the game. To this day, it's still my ringtone of choice.
Finally, I have to recommend "One Night in Neo Kobe City" from the Sega-CD version of the underground hit Snatcher. Never before has cheesy funk / synth pop sounded so good, and if you manage to see the intro that accompanies it you'll appreciate just how perfect the music was. Geekgasm ends.

The Halo series has amazing music. (I own all the soundtracks)

And basically any of the Final Fantasy's...

I liked VIII's... VII's was good... but then Advent Children redid them all and made them even better! (Sephiroth's theme!)

Lemmings and Street Fighter 2 are what immediately come to mind for pure midi catchiness. Wipeout also had a great soundtrack that was perfect for the game.

The Unreal music, I believe his name were Michiel Van Der Bos

for original soundtracks i'd say that the halo series and metroid prime series stand out as of recent. especially the original metroid prime. when it comes to lisenced soundtracks, tony hawk always does a good job of going through music and picking awesome songs, and i think that nothing has to be said about gta's abillity to do that.

SHADOW OF THE COLOSSUS - Absolutely amazing soundtrack by Kô Ôtani, one of the best I heard in a game. The Colossus battles wouldn't be as epic without it.

ELDER SCROLLS IV: OBLIVION - Jeremy Soule perfectly captured the world of Oblivion in music. To travel across Cyrodill listening to the soundtrack is a pleasure.

BIOSHOCK - The moment Rapture is seen for the first time is a memorable moment in gaming, thanks in great part to the music by Garry Schyman, which remains efficient throughout the rest of the game.

MAFIA: THE CITY OF LOST HEAVEN - One of the best stories in gaming had an equally masterful soundtrack by Vladimir Simunek, who avoided Godfather-inspired notes and created something original and unique.

FABLE: THE LOST CHAPTERS - The main theme by the usually excellent Danny Elfman is a little generic but good nonetheless, and the rest of the soundtrack by Russell Shaw is a wonder to listen to.

GIANTS: CITIZEN KABUTO - The main theme is iconic, and most of the soundtrack by Jeremy Soule and Mark Morgan suits the game well.

PRINCE OF PERSIA: THE SANDS OF TIME - Stuart Chatwood's music is great without being generic, and there's some memorable tracks.

METAL GEAR SOLID 3: SNAKE EATER - The main theme, 007-inspired, is fantastic. The rest of the music (composed by Harry Gregson-Williams) is very good. Metal Gear Solid 2 also deserves a mention.

ROME: TOTAL WAR - Jeff van Dyck's epic music makes the battles memorable, and the calm, slow music during the turn-based management part of the game manages to be excellent as well.

Hell March 2 from Red Alert 2. That justified the entire sound track.

Anything by Jeremy Soule.
Icewind Dale (Just so the guys on Page 2 know they are not alone. Inon Zur did an awsome job on the second game)
Both KOTOR games
Morrowind and Oblivion

What a great composer.

i am partial to the age of empires2 soundtrack for some bizzare reason and i am also very keen on the final fantasyX soundtrack, thats very good

but the best in opinion is the Dirge of Cerberus soundtrack especially the theme song by gackt

I would have to say... Wild Arms 2. The intro music is awesome. Zone Of The Enders 2nd Runner, because the mix of orchestra and classical music was very well done. The Metal Gear Solid theme is one of my favorite orchestral pieces ever, and I have several different versions of it on my iPod. PaRappa The Rapper had one of the coolest soundtracks ever (it was original music, shut up). Shadow of The Colossus, because it was amazing how much emotion the music carried. Oh, and how could I forget. The Myst Series has some of the greatest music ever written by mortal hands. If you walked up to almost anyone who owned a mac in the 90's and sang "Dun Dun, dun dun" (you know what I'm talking about), they would smile and give you a high five. Finally, Silent Hill, as the OP said.

Fire Emblem: Radiant Dawn. One of the best soundtracks I've ever heard.

http://www.youtube.com/profile_videos?user=treythemovie

That account has pretty much the entire soundtrack on it.

http://www.youtube.com/watch?v=C39CUQtWIzA

By far the best song from the game IMO.

HALO, Snake Eater and Ice Wind Dale are good.
But I find the game songs I listen to the most are from GoldenEye 64, that first level of Turok 2 and this really obscure 90s game called Traffic Department 2197.

F-Zero GX
Super Metroid (Relics of the Chozo) mix

The main theme from Morrowind still sends a shiver down my spine, although most of the music in that game is pretty generic classical stuff. The music in the last three GTA games was pretty sweet, I particularly enjoyed some of the cheesy country music in San Andreas, despite having a general hatred for that genre it just seemed to fit somehow with the mood of the game. The music from the original mechwarrior games (whatever happened to that series?) was also pretty amazing.