I know thermoreactive isn't really a word but that's not the point. The point is it's the one word that truly fits. There's a company that makes this paint for cars and it changes color as a reaction to heat. I'm down in the states...deep down...and we get a lot of crazy weather, hot and cold. I think this will be a big thing down here. What do you guys think?
http://alsacorp.com/products/eclipse/eclipse_vid.htm