LootHunter: Also, don't forget Black Mesa - which is a Half-Life remake in Source engine that uses all it's technoligies.
Great remake, even though Xen is missing for now (not a biggie if you've played the original). Still, it's a great experience for all FPS fans and a game I'd gladly buy if it came here on GOG (because I guess the possibility of a HL1 release here is slim to none...).
Johnmourby: Maybe I'm nostalgia blinded but four years on It's still in my ten favourite games.
Four? It's been in my ten favourite games since it's release! :P
tritone: I don't believe the OB included the original Half-Life, did it?
Nope. They added a whole lot of steam in there, but forgot to add HL1. :P