well, I was just joking John...

What you basically need, is the wheel connected to something that spins.... like an old bicycle speedometer. This is turn needs to crank a small turbine, which runs into a transformer to up the voltage. Then run that into a battery, sorta like a trickle charge. then use that battery to power things. the transformer, (basically a square magnet, with wires wrapped around, will have to be pretty big to turn the small amount of energy from the wheel into something half useful.

Thats about as far as my grade 12 science will take me.

Steve