After playing through Penumbra with the trusty glowstick (never found much use for the flashlight), I was driven to get a glowstick for myself. Chemical ones are wasteful, I didn't like the light diffusion of most LED ones, and the nicer Krill ones are kinda pricey. 
After some thought, I hobbled together part of a flashlight, some plain paper, a marker and some tape, and ended up with this. Great light output for getting around the house at night. I can see quite well, but I still am adjusted to the dark. Linky to a short demo vid. 
http://www.mediafire.com/?v2tfjca6i1n8pee