I was browsing Reddit and I stumbled upon this. It is a video on making duct tape glow a blue light by pulling two pieces of duct tape apart. Appearntly the glowing is caused by something called Triboluminescence.
Triboluminescence is an optical phenomenon in which light is generated through the breaking of chemical bonds in a material when it is pulled apart, ripped, scratched, crushed, or rubbed. The phenomenon is not fully understood, but appears to be caused by the separation and reunification of electrical charges. (Wikipedia)
This doesn't tell me very much, mostly because I don't fully understand what "separation and reunification of electrical charges." really means. So can anyone explain how seperation and reunification of electric charges can give rise to this blue glow?