Team Fortress 2 free this weekend!

Aug 12 - Valve, creators of award-winning games and leading technologies, today announced the unveiling of details for the largest update ever produced for Team Fortress 2, the multiplayer action game that recently topped PC Gamer UK's "Top 100" list.

Beginning today gamers may find details of "The Heavy" Update being disclosed via The site will reveal new information and screenshots each day, as well as a special installment to the "Meet the Team" series of video shorts.

"The Heavy" update is the largest update to Team Fortress 2 since it was first released as part of The Orange Box last October. In addition to offering new unlockable weapons, achievements, "The Heavy" update also includes a brand new gameplay mode and a number of new maps.
The rollout culminates next Tuesday, August 19 when the update will be made available to all owners of Team Fortress 2.

To give all gamers a chance to check out the new gameplay introduced in "The Heavy" update, Valve will be running a Team Fortress 2 Free Weekend via Steam, a leading online platform for the delivery and management of PC games. The Free Weekend is open to gamers the world over and scheduled to begin Friday, August 22 at 11 am PDT.

Team Fortress is one of Valve's most successful franchises, and features many classes to combat with as allies and as enemies.  All you need to do is download Steam, sign up for a free Steam account (a link appears when you start Steam), and then pre-load TF2.  More info about the game and update can be found at the links below.

Info about Team Fortress 2 (Wikipedia)
More info on TF2 (GiantBomb)
Team Fortress 2 free weekend info (official site)