I had a cat - just a plain long-hair tabby - that was hands down the coolest little guy I've ever known. I taught him how to open those old-house round doorknobs, open cupboard latches, flush toilets, sit, beg, and Wax-on, Wax-off and Paint the Fence from the Karate Kid. He got cancer and I had to do the last kind thing for him... that was about two months ago. He was almost fifteen and I got him as a kitten. I doubt I will ever, ever know another animal as special as he was.
In many ways he transcended being simply a 'pet.'