One of the more dangerous drugs available to Trolls, slide is first mentioned in Thud!. In Ankh-Morpork, it has begun to replace the dominance of Slab as the troll stimulant of choice. Sounding somewhat similar to crack cocaine, Slide causes trolls to go on a rampage and think they can take on the world. They then think they have no need for sleep, or food, or drink, and soon enough, they have no need for life.
Chrysoprase claims that because of the increasing predominance of Slide, he has gotten out of the drugs business. In an effort to prove his sincerity, he turns a troll drug laboratory over to Sam Vimes, who cynically notes that there's no profit in killing your customers.