My cats would not tolerate being dressed, I don't think. So I don't plan on dressing them up, though I do contemplate what I would dress them up as for Halloween if they WOULD tolerate it.
My parents' jack russell, though.. he loves wearing his blanket (it's like a horse blanket) in the winter, and would probably love wearing a sweater or jacket (we don't choose those, though, because he gets into burrs and luckily they don't stick to the outside of his blanket). He gets really cold with his short, thin coat and snuggles in to his blanket right away when you present it. His blanket is orange (we live where people could conceivably hunt), so he could easily be made into a pumpkin.