Altec Lansing iM207 Orbit-MP3 Speaker for iPod & MP3 Players for $9.99, plus $1.99 shipping for a total of $11.98 shipped. Here is a screenshot for your reference. It provides up to 24 hours of play on 3 AAA batteries (not included). Alternatively, it is available on Amazon for $14.99 with free shipping on orders over $25. Most places have it for about $29.