These jeans, by Naked and Famous, start off blue, and then transform to white with heat. How is this achieved? Well simply by including a “a thermo chromic dyestuff that has a molecule inside, which changes color based on its temperature range." So if you have a cold day outside, you'll have blue jeans. If you have a hot summer day, you'll have white jeans!

You'll have to suffer a bit though as retailers such as Barneys are selling them for $240 a pair.

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