Since it was suggested over IRC I thought it'd be good to strart the list.
Those are my games:
Carmageddon 2
Heretic
Hexen
Hexen II
Ground Control
Jazz Jackrabbit 2
Outpost 2
Star Craft: Brood War
Warcraft 3: The Frozen Throne
No need to mention they're all leeched, right?...
Plese, make your lists, so we can play sometime.
PS: Credit for the title goes to fourthgen