I tend, with no data whatsoever, to believe Blake that with a bit of selective breeding, we could get some miniature or toy cats - nevermind the small gene pool.
I suggest we start with lions, to capitalize on their social instincts.
What could be better than a cute, loyal, 12-inch high king of the beasts?
sounds like my girlfriend
First of all, while cheetahs are difficult to breed in captivity, there have been some successes in this endeavor. http://www.cheetah.org/?html=news-press&data=news-press&key=57
Like cheetahs, many other wild cats are difficult to breed in captivity. Amongst the smaller of these which may at first seem good candidates for domestication are the african golden cat, the asiatic golden cat, the clouded leopard, the jungle cat (which is not physiologically suited for ground dwelling).
One of the smallest cat species, and therefore one would think most readily domesticated, has a fierce temper and has been known to attack and bring down prey four times it’s size.
Species that have been somewhat domesticated include cheetahs, as mentioned above, caracels, the african wild cat, the jungle cat (possibly?).
http://www.wildcatconservation.org/cats/index.shtml
So there are cats that aren’t suitable for domestication due to physiological reasons (tree dwellers, size), temperment, and breeding behaviours, and then there are the species that live in areas where historically there has been little human interaction.
Is it possible to breed “hunting instinct” out of cats? My cats still hunt cockroaches, geckoes, lizards, and each other (but not mice, durnit).
Seems to me that a pet big enough to kill the neighbors’ pets and children for fun could be fairly inconvenient.
We just need to mate them with a pot-bellied pig.
Indeed. Ever see that home video of the mountain lion jumping into a SoCal resident’s back yard, grabbing their dog in its mouth, and jumping back over the wall. Imagine that’s your cat. Liability issues would be considerable.
But breeding hunting out of a cat? Seems like breeding swimming out of fish.
[devil’s advocate] Do you suppose someone once said the same about wolves? [/da]
Sure. And those who wouldn’t listen have given us the Toy Poodle. 
Cats have 38 chromosomes, dogs have 78. I’ve heard it theorized that there’s a greater variation among dog breeds than cat breeds because there are more ways to mix up a dog’s genome.
IANA genetic scientist of domesticated animals
I still suspect that the cats domesticated us.
I agree that cats are NOT domedticated…they are tamed. Dogs are domesticated. Ads proof, I cite my own experience. My sister-in-law’s cat appears to be quite friendly-except that it will bite and scratch you when you play with it. My dog on the other hand: Buddy and I play together a lot…and when things get rough, he will sometimes grab my hand in his mouth. However, as soon as he feels his teeth chomping down-he will back off-he obviously doesn’t want to hurt me.
That’s the difference…and a 100-lb. pet cat would probably rip you apart!