Who need an Apple Hi-Fi? It can't even go in the bathtub with you. This waterproof box has small speaker and a connection for the headphone jack to turn your iPod into a small boombox. Even though it does actually float I would still be reluctant to toss my beloved iPod into the water. It may not have as much "boom" as the Apple Hi-Fi, but it's over $300 cheaper and won't kill you to boot. It is available at Brookstone stores and should be available soon online.
iFloat waterproof speaker case [Popgadget]