- An exercise bike/ treadmill rigged to a dynamo. This will also give you an incentive to work out.
- Rather than using the microwave oven/convection oven which will eat into their function, you can place a small chimney over the cooking place (though the escaping vapors might pose a problem).
- I dontdon't exactly know how, but people sit on the couch all day. I know that itsit's potential energy, but something could be achieved there.
- The door idea from the above answers is great.
- Tiny wind mills in the patio.
- Solar cells (available on the cheap now) can be used outside.
- Craziest: Using a small turbine under the shower/tap