The Pedgen I. David Butcher has built himself an electricity maker (here he is on a prototype not watching television). He hopes to release the plans shortly. Possibly only masochists need apply?
Every morning, I pedal to generate electricity. The pedal generator charges batteries, that run an inverter, that produces 110v AC, that powers the monitor on my computer, and many other small battery-powered things. It is the most inspiring workout you can imagine.