FOOD/DRINK
Ataxia: A strong, Slaadi-produced alcohol brewed from pure chaos. Once someone is intoxicated by this beverage, they experience a temporary (but extreme) alignment shift to Chaotic Neutral, acting very aggressively and impulsively. (Fort DC 15)
Brimrum: A strong, yugoloth-produced alcohol brewed from pure spite. As ataxia, but consumers become Neutral Evil.
Calculus: A strong, modron-produced alcohol brewed from pure order. As ataxia, but consumers become Lawful Neutral.
Rainbow Slaadi: An Ataxia-based mixed drink, strained through a portable hole and a bag of holding. If it doesn't explode the universe, it's a strong but tasty drink which causes reality-altering hallucinations (i.e., everything you think you see, everyone else does, too).
Saturnalia: An alcoholic beverage brewed by Satyrs, explicitly to seduce nymphs. It's pink and very tasty, making it both attractive to the eye and disguising it strong alcoholic content. Being drunk on Saturnalia is has the side effect of a very mild mind-affecting suggestion ("you're horny"). (Fort DC 15)
Zephyril: A strong, Deva-produced alcohol brewed from pure benevolence. As ataxia, but consumers become Neutral Good.
DRUGS
Grave Earth (Extreme addictiveness, DC 25): An incredibly addictive drug made of the cremains of ghouls. The users become ghouls themselves after O.D.'ing, and remain addicted. Initial effect: Euphoria and lethargy Secondary Effect: 2d6 temp con damage, 1d6 temp Wis damage. Side effects: those that die of an overdose will rise as a ghoul. Overdose: secondary effect is cumulative, no other overdose effect
GAMES
Clue: It's the same game you play at home, but the Sigil version has such characters as Ms. Mauve, Mr. Green (the steak knife salesman), Mr. White, Vinnie Victim, and Colonel Cornhusk. He did it with the +2 battleaxe, in the water trap.