Valve start Team Fortress 2 Free Weekend on Steam
Continuing their efforts of offering rather cool stuff on each and every weekend, Valve will be having a free to play weekend for Team Fortress 2. It seems the event has already kicked-off, so you can head over here, and start downloading now right away. The PC specs are all on that page too, so you can check your PC can run the game beofre you commit to download
Once the event is over, you will have to pay €19,99 / £12.99 to keep playing. The game is said to be highly blooming addictive, so be warned!