If you watch 'The Late Show' regularly, you just might recognize Stephanie Birkitt. She appeared countless times on the program, in skits as herself and as a gift certificate-bearing assistant named "Vicki." Birkitt is also reportedly the woman at the center of an alleged extortion plot against her ex-boss, David Letterman, who Thursday admitted to having sexual relationships with several of his female staffers. Two segments featuring Birkitt over the years:


Dancing for Dave

"Vicki"