His hands are constantly cold and wet from being in his mouth. He can have a ton of toys around him, but won't pay much attention to any of them unless they accidentally get stuck on his hand.
He likes his feet too and has started reaching for them also. However, they don't quite reach his mouth, so they aren't as entertaining as his hands. He loves his feet the most when he can splash them in the tub.
And, just this last Sunday he realized he didn't have to put up with "tummy time" anymore and started rolling from his belly to his back.