made my own for a while using translucent nocks and tils bobber lights. but I would put so much time into making them and the battery wouldn't last or the switch would get damaged...so I switched to tracers. tracers are magnet activated and I lost a few of the magnets. ended up sewing a neodymium magnet into the index finger of my bow-hand glove... worked great for a year. then the batteries died on tracers (even though I had 'deactivated' them at the end of the season.
thought about switching to Firenocks since there are no switches to break, no magnets to loose, and the batteries are replaceable....but I just got sick of all the hassle and went back to standard florescent nocks.