The Team Fortress 2 update for the Spy and Sniper classes will go live tomorrow and to spoil you even further, Valve will make the game free to play through Steam this weekend.

The TF2 game files are now available for pre-loading so you'll be ready to play as soon as the free weekend begins. The free play period begins on Thursday and presumably lasts until Monday. Considering us Yanks have a long weekend from Memorial Day, that's a whole lot of free gaming.

The Sniper/Spy update adds new unlockable items and Achievements for each class. It comes with a new game mode and two maps as well.