+ Oh, so true +
From http://www.americanbaby.com for this week:
"Baby's understanding of "no" will soon extend to using it himself, either in words or through a definitive shake of the head. Although he's probably not yet sure what it means, it feels natural to him to move his head from side to side rather than up and down--which means that it will take him longer to grasp the concept of "yes." Once he understands about "no," he'll practice refusing everything from baths to diapers to his favorite meals...

As soon as your baby grasps the concept of "no," he will start playing with it as if it's an interesting new toy. To elicit a "no" (and the attention that comes with it), he'll bang on tables and chairs, pull at your clothes, or head for objects that you've placed off-limits, such as the computer or phone cord. If you don't say "no" fast enough, he'll slow his pace, give you a big smile, and continue on his way. The point of this game isn't to reach the forbidden item--it's to interact with you. And the best way to handle it isn't punishment, but providing safe, alternative ways to play together. "

You've been frantically shaking your head no for a couple of weeks now. Lovely new trick, really. You think it's hysterical. And a couple of days ago, it really dawned on me that you are trying it - and us - out. You totally do that thing where you crawl a few feet, stop, turn to look at us with a devilish grin as if daring us to say no, then crawl a few more feet... Wash, rinse, repeat. VERY cute. Exhausting, but very cute.