I used to work for a friend's parents, who were in the fresh herb import business. They were interested in getting into peppers, particularily habenaro. We received a shipment one day, and I'll never forget it.
I opened the case and just breathing the little blighters in caused my nose to burn a bit. Soon, we found ourselves throwing them at each other. Contact with skin would leave a burn. I made the mistake of wiping my forehead with my arm and the burning was so intense I had to sit down.
Later, we dared an idiot driver to try one. Trying to impress us, he bit one in half and swallowed it. His face immediately went red and he began to vomit. We quickly gave him milk.