1. TEAM FORTRESS 2 
And the Number 1 Free PC Game of 2011 is...Team Fortress 2! Come on, it was released in 2007, why is it in the list now? Well, you are in for a surprise. This smash hit game from Valve is now free to play! Seriously? You mean the same team who made Counter Strike, Left4Dead, Half Life and the Portal series is offering a free game! Look no further, because as of June 2011, TF2, one of the most critically acclaimed games of all time, is free to play!
**** READ OUR FULL REVIEW ****
Download: http://www.tf2.com/freetoplay/
Genre: Action, FPS, Multiplayer, Team Based