The ceramic color-changing, heat-sensitive ashtray is green to start with...whens its heated up a little it turns amber, and when its fire-hazzard-hot it turns red. This would be great as a safety feature when emptying it out. Green -> go, Red -> no. This would also have the added novelty benefit of a color changing ashtray. Could be made using te same technology that some of the newer concept cars use with their brake discs. As they heat up, they glow.
-- shinobi, May 30 2004

Wow. Six years and no anno. (+)
-- 2 fries shy of a happy meal, Nov 23 2010



random, halfbakery