I'll be chronicling my adventures in designing a usable and useful power system, powered by spinning wheels. I'm only just starting out so, though it should be "finished" in a week or fifty, I'll start by outlining my ideas.

1. Neodymium magnets can be found very cheap (by America-or-wealthier standards) and same for copper wire. 32ga magnet wire coiled into tiny giants, epoxied to a PVC circle and being passed within a small brush of the B field from some magnets I've JB-Welded to the spokes, should induce enough current to rectify-ify into a phone charge pretty easily. EMF is related to the number of turns of wire, and the time rate of change of magnetic flux, so I'm still trying to reconcile coil size with efficiency.