I had that the other day. Was laying without a top on in bed watching Look Who's Talking and I fancied a drink, so I undid my bottle and put the lid on my tummy, suddenly I saw it shoot over to the other side of the room!
Then I tried to make her do it again and I saw my tummy spasm, then I wanted her to do it again to video it but she wouldn't. The sausage =P