Early in our wedding process we purchased 20 of these awesome 12" glass fishing floats as a decoration for our beach wedding. This was probably (ok, definitely) a foolish late night impulse buy from Coldwater Creek's end of year clearance sale, and a week later we received 20 double-boxed floats that reduced our 500 sqft basement apartment into a 250 sqft basement apartment.
Continuing down the path of foolishness, I thought that it would be a great idea to make 20 firefly circuits for each of these floats, all on my own; not like I had any other wedding planning to do, right? Between cake flavors and seating charts, the fireflies were back-burnered till a month before the wedding. Offering bribes of pizza and beer, I roped together any friends I could to put them together; for many it was a harsh introduction to the world of soldering.
Making 20, I decided it made enough sense to print my own PCB, and why not have that PCB mount directly to the battery board! It worked out really well and I owe a great deal of thanks to Laen from our dorkbot group in Portland, OR for printing these PCBs for me. You'll find the eagle files attached if you care to make your own. You'll want to use Mouser #614-HU2430-LF For holding the battery, all the other parts are identical to the original.
The fireflies were a hit and it made for a terrific memorable project.