I will be doing my thing -picking up toys, washing dishes, etc.- and out of the blue, WHACK, his hand (or one the of kids toys, or a wooden spoon, or the damn kitchen towel) meet up with my ass for quick, "howdy-do?"
Most times, he will wait long enough to see the look on my face. Sometimes, he is already walking away by the time I turn around. Every once in awhile, he sticks around for a couple more howdy-do's.
No matter what happens afterwards, smugness radiates off of him.
I try to be upset (because it hurts, darn it), but it never works. I just love that smugness too much.