The Greenhouse Effect, melting polar ice caps, rising sea levels - it's all serious stuff. Just to hammer the message home you can now watch continents shrink as you drink your tea.
The Global Warming Mug comes printed with a map of the world. When you add hot water, watch and see the contours of the landmass change as sea-levels rise.
When the hot drink is gone and the mug cools down, land reappears again - if only it was that simple in real life!
The Global Warming Mug is not suitable for washing in a dishwasher. You can tell yourself you're saving some electricity as you rinse it by hand.