Burning Man 2011 project #1 finished!
I still need to get the battery sorted but I’ll do that when I get over to the States (batteries look like Semtex to airport luggage scanners and I can do without that excitement.)

These are the bike underlights. Couple of LED strips and 700mA constant current drivers from Deal Extreme, encased in perspex pipe and sealed with E6000 (a recommendation of the fantastic Dr. Jon’s Guide to Electronics on the Playa.)
They’re really, really bright and hopefully they’ll reflect well off the playa surface at night.