Apparently, hands are for things. Shocking, I know, but hands can actually be controlled and used for grabbing interesting objects - not just grasping them when they're put in your hand, but actually reaching out and taking them. See:
Jim sees a thing.
Jim reaches for the thing.
Jim has it IN HIS CONTROL. *maniacal laughter, etc*
This, of course, means that nothing is safe. His absolute favorite thing to grab is my hair, and he won't relinquish it without a good deal of prying. He hasn't yet grabbed Bruce's tail, but I think it's only a matter of time.