The Conscience advisors in Black & White 1 and 2 (Although sometimes their dialogue got annoying >.> ), I loved in the first one how you could spin your mouse around the screen on the tutorial and the Evil advisor would spin his head randomly with the mouse.
The Minions in Overlord (They all rock, except that old hunchback minion.)
Kane from CnC. You can't argue with him, his goatee, his silver Nod ring and shiny dome.
Iron Man from his movie game, although the person who plays Tony Starks voice in the game is NOT Robert Downey Jr., which sucks big time.