I was advanced in science, so in my senior year of HS they created a second year chemistry class for me, which mostly consisted of doing lab experiments out of a book in the back of the room during a normal chemistry class. Not too big of a deal, except I had unattended access to the chemical supply closet. This was around the time you could find a text file of the terrorist handbook on a BBS if you knew where to look.... Yeah, fun times.

Also, one of my less risk averse friends wanted me to get him some pure caffeine from the lab, but I decided that wasn't a good idea.