I have some really fine craft glue leftover from making christmas ornaments with my kids. I wonder if it would work? That shiz was everywhere when we were done. I'm willing to bet it'd stick to a layer of roo sweat no problem.
and btw, the glowbys are AWESOME. I had to hide them from my 5yo because she is convinced I got them for her. How awkward was it when she told her brother's teacher that mommy has light up hair for Bonnaroo. Makes me sound real mature and motherly.
PS the white and green are MUCH brighter than the red and pink glowbys. The whole thing glows in green and white, whereas the red and pink really only show color on the tips. Both are cool though. I can attempt pics of what I have. I'm waiting on 4 more in the mail, too.