All the girlfriends and ex-girlfriends Seinfeld had on the show. The fictional Jerry Seinfeld had everything from relationships to flings to hookups, providing much comedic fodder. Most of Seinfeld's girlfriends had a hilarious trait that would really bug him AND the audience.
Teri Hatcher (her breasts were real, and they were "spectacular")
Courtney Cox (abused Jerry's dry-cleaning discount)