Btw, I am EXTREMELY psyched about Portal. After playing an old game of the same style (Narbacular Drop, its not worth downloading, beatable in like 10 minutes) I thought it was an amazing premise for a game, and totally mind-bending - after just playing for a little while, you actually began to 'think in portals', as is Portal's slogan; what you might do, how to accomplish certain things, and what totally absurd and amazing things you could do given that ability. Some of the best fun I had was placin a portal in the ceiling, one on the floor below it, jumping in, and falling indefinitely, reaching amazing speeds. Then, as you fall through the room to the portal below you, place a new portal (to replace the one on the ceiling) right next to the one on the floor- you'd enter the one that is already placed and your current neck-break speed, and shoot out the other one (now on the floor) with an upward trajectory flying just as fast. Is pretty awesome, til you hit something^^
Edit: TF2, haha. That is being released in a pack with Portal, unless things have changed since I read that, and will be one thing that is a guaranteed buy for me already.