turbodog
Flashaholic
I am not doing this myself, but posted it here for someone else to experiment with. Take the led assembly out of a uk4aaeled and fabricate some sort of battery tube for it. Mine will run off of a 123 cell, but I don't know for how long or at what brightness. In any case, if someone could do this, you'd have a low cost 1 watt light that could be shorter than 3" with a twist pak. And that's pretty nice.