Goal: An absurd array of bike lights, both functional (illuminating path ahead, safety lights to notify others of my presence) and decorative (just want to have an absurd number of lights that look cool and space-age =]). I want a run time - with everything switched on - of at least four hours. Conserving power by switching off purely decorative lights should get me to 12 hours (i.e., an entire night).
So far: I've demonstrated that a small 12v battery can be charged for ~six hours on an overcast day, and run an extremely bright strobe for more than 12 hours (was still running when I unhooked it). A good start!
Next: Convert some standard bike LED bike lights to run off the 12v source. This requires that I solve the problem of powering a 3v (or whatever) bike light with a 12v battery. I'm assuming that I just stick resistors in the circuit to get to the appropriate voltage, but I need to do some more research/tests. Here's an LED circuitry tutorial that seems to validate my basic theory.