I undoubtedly did permanent damage to my tooth enamel eating mass quantities of super sour candies. I remember puckering so hard I couldn't see straight -- and I loved it. It looks like the sour candy arms race has only escalated since I was a child too -- just look at this:
Yes, that's right: Toxic Waste Candy. Their slogan is "hazardously sour candy." Their website is themed like a nuclear power plant, and they feature pucker-videos where people try the Toxic Waste Challenge on camera and record their reactions:
You know, we live in a crazy world: feed your toddler battery acid, you're going to jail for child abuse. Feed him Toxic Waste, and that's some funny Youtube right there!