I bought this speaker, it uses 4 AA batteries, which last a very long time, the sound quality is excellent, with a lot of volume available. It is also very light, well built, and portable. Uses a 3.5mm headphone plug. Even comes with a carry pouch and cable. $29.99 + $4.99 shipping.
http://www.tigerdirect.com/applicati...MP=OTC-FROOGLE