I got eleven flash circuit boards from The Electronics Goldmine. They were on sale for $0.79 (79 cents, or PHP 38) each. I bought ten and got eleven.
Each one has a 160uF or 120uF photoflash capacitor, rated at 330V, a tiny inverter, and flash circuitry. It only needs a single 1.5V AA battery to operate. The process is simple: put the battery in, with positive facing the circuit board, depress the metal "diving board" switch on the PCB itself to charge up the capacitor, then short the two dangling wires to fire the flash.
Trivial! I think it's about Guide Number 6 to 8. Quite minimal, but people have made super cheap DIY ring flashes out of these babies.
For my purposes, I'll put five flashes into each ring flash (made from the bottom of a KFC plastic meal bucket). This will also give me two semi-powerful flashes for my ghetto studio.
First order of business was to remove the battery clips, permanently short the flash power switch, and wire the flashes together. I also have to parallel the trigger wires so that the five flashes can be fired simultaneously. So far I've only done the first two steps:
If I'm lucky, I'll get some results this weekend!