Jason Holt's put together a gadget board, a prototyping board based on the Atmel microcontroller (see photo). His design has a built-in monitor program for controlling the board. The I/O features eight analog inputs, seven 0-5v inputs and one input with adjustable max voltage, eight high current MOSFET outputs, and 4 high current relays. Jason's offering the schematics, code, and instructions for free or will also sell you a completed board.