I also sandpapered my LEDs and placed them directly on a cap with a power supply that uses two double a batteries and a switch, all wires are hidden very nicely with only diodes showing in very similar places as those suggested by freetrack (much like the caps the guy at freetrack forum makes and sells). Even with sandpapered / polished diodes i found the negative photo film better than the floppy disk solution, in fact my glasses and the cap i used for tests, which was white, reflected lots of light that got through the floppy disk. all this was fixed with the photo film and switching to a black cap. i'm interested though, in the Wii mote / ps3 eyecam alternatives.