The Regen Reverb Solar Powered iPod Dock is 3 feet tall, and it can apparently pump out 60 watts of power, and can play  music for up to 12 hours.
It can also be recharged via mains power, and it is compatible with the iPhone and the majority of iPods, and it also comes with a 3.5mm audio jack so you can use any MP3 player with it.

The Regen Reverb Solar Powered iPod Dock will go on sale in April 2010 for  $2,299