Elvis
El or Ellie
Pretty Boy
When he's being bad, my roommate calls him Elsama (bin Laden)

Jack Daniel
Danny
WC (Wreckin' Crew - because he's the one-cat wreckin' crew. That boy gets into EVERYTHING)
Chubsy, because he's getting really FAT!
My roommate has started calling him "Gump", because he's not exactly the brightest star in the galaxy. LOL.