When I was a kid, a friend of mine and I used to play with flourescent tubes under power lines. Some people didn't believe me when I told them the tubes would light up.
Check out the Richard Box website.
FYI, the small ones (about 7-8 inches long) that are made for battery-powered lanterns will glow so bright you can sit down and read by them. The big ones didn't glow quite so bright, but were bright enough that they were clearly visible in the darkness.