Swank: Ten times as addictive as marijuana. To human misery! -The Simpsons
Bliss: The stuff used at the beginning of Red Dwarf sounds an awful lot like cocaine.
Otrozone: Red Dwarf again. Looks like heroin for androids, judging by the effects.
Android Home Brew: Lethal to humans but it's then it's probably also lethal to androids as well but that doesn't matter because it's The Last Day. Red Dwarf. Man there was a lot of drug use for a show with six episodes per season.
The performance enhancing gas that Norman Osbourne inhales to become the Green Goblin in Spiderman. I think the initials were PCP but I wouldn't be surprised if it actually was Angel Dust. Fucked him up pretty good it did, I mean look at those cool weapons! I'm pretty sure some of the other villains were on something too.
The Pan-Galactic Gargleblasters from Hitchhickers Guide to the Galaxy. Also, every race in the universe seems to have a drink pronounced 'gin and tonics'.
Pretty much anything consumed in Alice in Wonderland!
Zyme from Deus Ex. It's played up like heroin but doing the stuff is like drinking all the alcohol in the game at once. Boring.
The steroid filled spinach Popeye eats all the time. I swear that guy's got no gonads left after eating so many steroids. But then it doesn't look like Olive Oyl can take much punishment in bed anyway, so it doesn't really matter whether or not he can perform.
I once dreamt I smoked...something. I think I had been reading a thread about DMT laced weed during the day so I must have been thinking of it. It wasn't DMT though. I dreamt I was in a friend's house with a bunch of other psychonauts. What happened was I loaded it into my ice pipe and vapourised it. Took a big drag, passed out and appeared in a sort of desert area behind another friend's house. Either the drug teleported me, I moved there myself without knowing or I imagined I was in some other world. Didn't dream long enough to find out, I woke up at around this point. I want some of whatever it was though.
That reminds me of one more - the way to Monkey Island. You put all those items in the cauldron, you pass out, wake up at Monkey Island!