The
agent Roger Thornhill was mistaken for in
Hitchcock's classic "
North By Northwest", starring
Cary Grant and
Eva Marie Saint. George Kaplan was a ficticious person - second cousin to
Harvey the Rabbit - that the government invented so that their real agent wasn't discovered. Cool movie.
Also the name of the leader of the Candy Bars (played by James Coburn) in the Bruce Willis classic "Hudson Hawk".