Other than that Kat-kat, Fatty (when he's in my way or such, LOL! Then it's "Fatty, MOVE!), Boogie (he's a little booger), Cody-Bee,and the others share most of his nicknames, lol. Oh, Bella aka Bella-Bee. I give each one a special nick name, from there-they share nicknames!
Princess: Boo (the most common), Boo Boo, Boo Boo bear, baby boo, pretty Princess, Pretty kitty, little stinker, and when she's at the vet her nickname name becomes psycho-kitty because she tries to kill anyone (other than me) when she's there.
Patsy: Fat cat, pretty kitty, love-bug, baby Patsy, killer kitty (when she's really into "stalking her toys"), patsy-watsy
Mikey: Mr. Mike, Mikey Moose, Moose, and when he's in trouble Michael.
Blackie: Blackster, Baby Blackie, fur-ball (she's nothing but fur), wackie-Blackie
George: Baby George, Georgie Porgie, George of the Jungle
There are more but those are the main ones I use (and all that I can think of).
I have so many! Right now they are.....pumpkin pie, precious pie, potato pie, chunky potato, lover, loverboy, my sweet baby, handsome man, poopy joe, punker, punk-rocker.....I know, I'm so weird.
Basically, just anything that comes to my mind at the moment. They change all the time.