College has gotten me to play more heavily on PC. I have three older consoles sitting in my dorm room collecting dust right now

I recently got Warcraft 2 to run on my mac. I'm very happy about that. Though the game is outdated as hell. I think the battle.net edition fixed some of the problems but it's much harder to play without those newer RTS design features (like queueing units, auto-attack, right clicking, ect.)
Starcraft 2 is amazing. Custom games are a blast and I've finally been able to play on the ladder and win. Just went on a 5 win streak in 1v1.
Left 4 Dead is great if you have friends who have it.
I've been playing some dragon age: origins but I don't like it as much as mass effect.
Homeworld 2 is a good game if you are looking for a 3d space combat RTS game. A little rough on the controls but otherwise a fun game.
Poker Night at the Inventory is great if you are a geek who likes Strong Bad from homestar runner, Tycho Brahe from Penny Arcade, Max from sam and max, and the Heavy from TF2.
Minecraft is just creepy good.