Wow, what a day for eco-friendly DIY speakers. Unlike the DIY speaker kit mentioned earlier, these solar portable speakers are not kits, you can make them using various speaker and solar parts mentioned in the DIY.
I have to say these solar portable speaker certainly rock over the previous one as it can power itself using the power of the sun.
Combine a small, energy efficient digital amplifier, cheap bookshelf speakers, batteries, a small solar panel, and your MP3 player as a source.
Fasten everything together, add a handle, and take it on the road!
This project makes for a fun, easy solar project, that will help you learn about how solar panel, and audio systems operate.