The Orange Box

The Orange Box is a bundle that includes five titles from Valve:

Half-Life 2, Half-Life 2 Supplement: Episode One, Half-Life 2 Supplement: Episode Two,
Portal, the game that blends puzzles, first person action, and adventure gaming to produce an experience like no other,
Team fortress 2, the sequel to the game that put class-based, multiplayer team warfare on the map.