In a world where computers are increasingly powerful and are concealed within ever more glossy slabs of aluminum, the Raspberry Pi (RPi) offers surprising proof for the virtue of moderation.

Resembling little more than a credit card-sized scrap of exposed circuit board, the RPi is a fully programmable PC that runs a free, open-source Linux operating system, plugs into any TV, can power 3D graphics, connects to the Internet and, with a little ingenuity, be used to create your own personalized robot slave.

The computer's miniature frame is crowded with two USB ports, an SD card slot, an Ethernet connection and microchip in the middle -- all powered by a universal USB mobile charger.