Heatswell – heat activated coffee cup insulation

[youtube http://www.youtube.com/watch?v=2F9O8YV_36Q&hl=en_US&fs=1&]
Heatswell via NOTCOT.

Pour a hot beverage like coffee, tea, hot chocolate or soup into this thin stackable coffee cup and watch its midsection swell to form a cool insulating collar – a 100% genuine endothermic reaction.