Risky Business: Warning spoilers ahead
I liked Guido (Joe Pantoliano) from Risky Business:
"In a sluggish economy, never ever fuck with another man's livelihood"
Guido lets Tom Cruise do all the pimping then rips off the furniture at Tom's house while Tom is off with Rebecca De Mornay.
Guido hangs up the phone on Tom everytime Tom raises his voice until Tom realizes he is powerless and must give up all his pimp earnings to get the furniture back.
Actually, the fav bad guy title should go to both Joe Pantoliano and Rebecca De Mornay because it looks like they were setting Tom up from the beginning.
Or maybe the bad guy is Tom Cruise for fucking with Guido's livelihood in the first place.
Chinatown spoilers ahead:
Ah fuck it, my most hated bad guy is Noah Cross (John Huston) from Chinatown. Fucking your daughter is bad - no ifs, ands or buts. To top it off, he gets away with it, and the movie ends with him getting custody of the granddaughter he made with his daughter. That guy is pure evil.
In summary,
Good bad guy: Guido
Bad bad guy: Noah Cross