The Steam Holiday sale is on now. Until January 2, every game on Steam is available at 10% to 75% off the regular price. Select publisher catalogs such as Ubisoft, THQ, and 2K Games are 25% off. Award-winning titles such as Bioshock and Portal are available for 75% off the regular price. For more information, please visit steamgames.com/holidaysale

This includes Left4Dead at only $37.49!