The word you're looking for on the Wint-O-Green Life Savers® thing is triboluminescence. (Bioluminescence refers to the cold light given off by some living organisms, such as the critters that glow in the nighttime wake of a moving vessel. It's also what makes fireflies and glowworms glow.)You can read a great explanation of it at http://daily.stanford.org/Daily96-97/4-2-97/NEWS/NEWbug02.html.

O.K. - encyclopædia mode off.