Ah crap, I accidentally uninstalled Counter-Strike: Source.
YOU F-f-*BRZZZ*-O-o-O-o-OOOOLLLL Y-y-J-u-Ou D-D-DoomED *Brzzt* US A-A-AAAaaaaa-AAAAAAAa*error*
YOU F-f-*BRZZZ*-O-o-O-o-OOOOLLLL Y-y-J-u-Ou D-D-DoomED *Brzzt* US A-A-AAAaaaaa-AAAAAAAa*error*