User blog comment:Pancake2/I just learned something the hard way - Read this so you won't have to!/@comment-2128395-20100902084746

Since we're all commenting about lights and our experiences; When I was a kid I would use this glow stick at night to sneak to bed to write in a journal I had. The glow stick was bright enough for me to see what I was writing but dim enough so my mom couldn't see from outside. The glow stick was green and after an hour of writing in green light later (with the glow stick right in my face, too), everything looked purple for the next 10 minutes.