A raisin dropped in a glass of fresh champagne will bounce up and down continuously from the bottom of the glass to the top.
Wanna see? Check out this video. Why does this happen? Apparently, it’s because the carbonation in the drink gets pockets of air stuck in the wrinkles of the raisin, which is light enough to be raised by this air. When it reaches the surface of the champagne, the bubbles pop, and the raisin sinks back to the bottom, starting the cycle over.