If you use the MobiBlu DAH-1500 mp3 player, you can now add a speaker to it that is exactly the same size as the player. Powered by a lithium polymer battery, it delivers up to 5 hours of music. Its output is 0.8 Watts and it comes with a retractable connector. The battery is recharged via USB.
The MobiBLU Cube Speake is available for $29.95 USD directly from MobiBLU, either in black or white.
Source: Ubergizmo