[MrForbes]

A little update...we never got around to making our little LM7805 cirucit properly, that is, we never secured the wires to anything, and one of the leads on the part broke off. Yesterday we got out an old 12v- 5v converter from a previous year KOP and wired it in place of the regulator chip, but kept the series resistor. seems to work fine.

Beam width on a light like this might be important, I expect there are several ways to get a spotlight effect. The spotlight we used with the reflector seems to be pretty good.