For me, it wasn't really on purpose
Anyone ever seen those pop-rocks things where you mix poprocks, water, and two other powders in a test-tube? Well, I was making one of those, and the ingredients weren't cooperating very well. I ended up accidentally drinking the entire packet of pure sour horribleness combined with tap water.
Once the entire concoction was in my mouth, I started puking (luckily it was outside) and afterwards I couldn't stop drooling for about half an hour.
My cousin, who was with me at the time, thought it was funny, and did the same thing with his sour packet thing to cheer me up. Needless to say, I was cheered up after he started drooling all over the place and swearing about poprocks for the next ten minutes.