Remember back in the 80s, when everyone wore those cheesy thermochromatic T-shirts? Yes, you know the ones! They were T-shirts that changed colour when subjected to heat. Basically, everyone knew when you were sweaty, because the underarms of your T-shirt would change colour! They were called Global Hypercolour and along with goaty beards, big hair and jelly shoes, they were a common sight on the streets of the UK for years.
