Bella does this all the time - usually when she wants to play. She will go across the room and look at me. If I put my hand up ("talk to the hand" style) she will go trance-like until one of us moves and then pounces toward me trying to attack my hand. She will do this 2-3 times in a row and usually with the paw up. I try not to do it too often because I don't want to encourage play-biting at all, but it's the cutest darn thing.
