Oooh BTDT! LOL It's a shocker isn't it!!! Jacob went through a stage of doing that too and I think it was simply one of those things he did just because he'd discovered that he could IYKWIM?

We found that the best thing to do was to ignore it, as the more attention we paid to it, the more he did it! It's pretty hard to ignore though....it's on the same scale as running your fingernails down a blackboard in my book ROFL! *shudder*