“Raspy Juice is an experimentor’s expansion board to power supply a Raspberry Pi (RPi) host computer with a DC-DC SMPS buck regulated +5V from a wide-range voltage source (such as batteries, 12V power adapters, solar batteries, etc). The board also contains an RTC real-time clock, an RS232 level translator to breakout the host console GPIO UART serial port, and an expansion AVR ATmega168A microcontroller (MCU). This expansion MCU interfaced to the host computer as an I2C slave device, provides the services of controlling 4 channels of RC servo outputs, an RS485 interface, and a half-duplex software-based RS232 interface. Additionally, the spare pins of the MCU are brought to an expansion header which may be used for other purposes. The MCU firmware is upgradeable by the host computer and may be reprogrammed for other application-specific purposes.”

Raspy Juice Rev.1 Beta Board | 2-Watt Elements.

The board costs 42 SGD (which is about £21) plus 10 SGD (so another £5 ish) for shipping. Not bad for a board that gives you all that.