The BerryPower(tm) is a tiny but powerful power controller perfect for older Raspberry Pi's (Model B) or for systems and applications where size is a concern.

With it's 5V, 2.5A output and the 2000 mAh battery, it has plenty of power for most applications. The on/off controller and other circuitry provide for safe shutdown when the power button (not provided) is pressed, or when the battery is about to run out. The open source BerryPower software and configuration documents are available from github.