A while back at an NA speaker meeting, the speaker shared that, when he took too many oxys and vomited, he would pick the undigested pills out of the toilet and eat them again.
I also met a girl in my residential rehab that, lacking citric acid, had shot crack in Kool-Aid. It turned her piss blue.
The dumbest thing I've ever done to get high is parachute several grams of nutmeg. Nutmeg! Instead of a high, I earned myself three days of vague nausea and body aches, and a permanent disgust for the taste of nutmeg. I knew getting high off nutmeg is a stupid, puerile urban legend, but in my defense I was living abroad with no access to drugs, and I reeeeeaaaalllly wanted to get out of my head for a few hours. Still, it's disgusting and embarrassing.
Oh, and when I had a bad needle fixation, I shot plenty of things that should not enter human veins: specks of dust and lint and skin in a poorly-filtered shot because there may have been specks of meth as I carpet-surfed desperately for four hours in the middle of the night; Seroquel, which gave me a slight high that I later learned is pure placebo, as quetiapine is not very water-soluble; Benadryl, which I reasoned would give me a ghost of a heroin high, as I'm used to dope cut with diphenhydramine, but instead made me woozy and uncomfortable; and of course straight-up water, because my addiction to the act of shooting up gave me a rush in itself.