There's nothing that'll put you in a better mood than watching 2 week old kittens crawl around. The biggest, a boy named Karl, is quite like a human baby at times. I held him a while, then when he wasn't noticably warmer than my hands, I put him back into the pile with his sisters (of the other 3, 2 are definitely girls). He rolled around his fat belly and mostly onto his back, then shook out one back leg, then looked at it.
"Yes, that's your leg."
He looked at it, then at me, then back at it while he shook it out some more. Then he put one front paw into his mouth and chewed on it a bit.
"Yes, that's your other leg, too."
After munching on his own toes a minute, he turned and munched on one of his sister's ears.
"Now, those are hers, be nice."
I love babies. :-)