A blisteringly fast speed run video has taken "thinking with portals" to a whole new level.
After two years of work, a Portal player called "DemonStrate" has managed to complete the game from start to finish in less than ten minutes. According to DemonStrate, his time of nine minutes and twenty five seconds is the current world record for a Portal speed run.
The run makes extensive use of the various glitches found in the game, from the speed boost gained by bunny hopping backwards while crouched, to essentially skipping the entire second half of the game by getting outside the map. The video isn't actually a single run through, as DemonStrate segmented it by map, but he asserts that each map was done in a single take.
As you can see by watching the video, it's actually quite hard to keep track of what's going on, as he bends and flips in seemingly random ways. He's even able to somehow get to the cake room and squash it with the companion cube while GLaDOS is in her death throes. Fortunately, he's also put together a series of companion videos, which explain the glitches he uses in more detail.