Here is a retro-style cassette stereo mini speaker for iPod and iPhone. The speaker offers stereo output and is battery free as it is powered by iPod/iPhone. It’s even smaller than a iPod nano.
The Retro speaker works with most iPod players, including iPhone 2G/3G/3GS, iPod touch 1G/2G, iPod nano all gen…etc. It is priced at $31.99.