I cracked open "The Orange Box" last night (for my 360)... The first thing I did was jump into Portal. At first, it didn't seem like much and was rather wacky. Once I got the hang of it, though, it was a blast. Seriously fun game -- just a shame it only took about 5 hours start to finish. I am going back to play "expert mode" now... I generally hate puzzle/platformer types, but this provides a unique angle on the puzzle idea.
I've never played any of the previous half-life titles before. I put in Half Life two and played a couple of hours. So far it's really cool.
If you haven't already purchased The Orange Box, I highly recommend you do so. Portal is almost worth the price of admission all by itself...
I hate trolls.
Systems I currently own: 360, PS3, Wii, DS Lite (2)
Systems I've owned: PS2, PS1, Dreamcast, Saturn, 3DO, Genesis, Gamecube, N64, SNES, NES, GBA, GB, C64, Amiga, Atari 2600 and 5200, Sega Game Gear, Vectrex, Intellivision, Pong. Yes, Pong.
