When I was 18 or so, I ate a few handfuls of LSD-laced gummy bears on accident. I like gummy bears, and they were just right next to my friend's computer. He stopped me after I had downed 20 or so.
I spent a few hours trying to claw my eyeballs out, and then spent the night and most of the morning hitch-hiking around his living room. I wasn't the same for a good month and a half.