No purchase necessary.

Team Fortress 2 screenshot

To celebrate the Spy/Sniper update coming today to Team Fortress 2 via Steam, Valve has announced it will make the game free to play over this coming weekend.

This gives all PC gamers the chance to experience the excellent class-based team FPS at no cost and you'll even get to try out the new Spy/Sniper update. You can pre-load the game now and should be able to start shooting down medics and such today.

You'll find more info over on Steampowered.com.