Users Playing this game are also playing:

Half-Life: Opposing Force
Half-Life: Opposing Force
Portal
Portal
Team Fortress 2
Team Fortress 2
Half-Life 2
Half-Life 2
Half-Life: Blue Shift
Half-Life: Blue Shift

Users who own this game also own:

Portal
Portal
AudioSurf
AudioSurf
Portal 2
Portal 2
Left 4 Dead 2
Left 4 Dead 2
Half-Life 2
Half-Life 2