TF2 went Free 2 Play a week or two back. This is the quintessential class based shooter. Has aged very well, and is better today on both PC and mac than it ever was on a console. Check out these incredibly funny promo videos.
Team Fortress 2
HoosierData
I used to be with ‘it’, but then they changed what ‘it’ was. Now what I’m with isn’t ‘it’ anymore and what’s ‘it’ seems weird and scary. It’ll happen to you!