Portal's a pretty short game. It might be the most-defining single player experience of this generation for me, but it still took me a few hours to finish it the first time. Last I tried to speedrun it, it took me 48 minutes, and I thought that was impressive, but gamer DemonStrate has completely blown me by the wayside, finishing the first person puzzler in a little over ten minutes.

Granted, he takes advantage of a ton of exploits and glitches found and discovered, but still, the last couple minutes is absolutely impressive in that "what the hell am I watching ?" way.

http://www.youtube.com/v/W1U5RUVENNE?fs=1&hl=en_US&rel=0

Taking down GlaDOS is particularly amazing. Bravo, DemonStrate; I can't even begin to compete with the skills you possess.