tl;dr: First time I nearly lit my apartment on fire by trying to boil water.

This time? I learned a valuable lesson about drain cleaners. [b][i]Read the fucking bottle in detail[/i][/b].

So I poured some drain cleaner into a glass to pour it down the drain, put it down for a minute to check something on my computer and came back... When I noticed something. It was leaking a little. I look at the bottom of the glass. The !@#$ing drain cleaner is so acidic it is [i]eating its way through glass[/i]. So I rush-pour it down the drain only to see a couple droplets rolling down the glass, which I promptly dropped in the sink.

So I check the bottle.

Professional strength drain cleaner. "Kay whate--" [b]"DO NOT POUR IN GLASS."[/b] Oh.

TIL: Read cleaner bottles.