* FridgeBrilliance: There's a passing mention in ''Discworld/{{Hogfather}}'' that pencils in Discworld aren't manufactured, but ''grown'' as stems of a type of bush native to Sumtri. Considering how many other utensils started sprouting from the Mono Island vegetation, it's quite possible that this is where that bush's ancestors came from.
** More FridgeBrilliance: Ponder's and Ridcully's discussion of how stepping on an ant might change the future takes on new depths of irony when you realize that they're only '''having''' the conversation ''because of a single ant.'' Specifically, the one that the Lady arranged to divert from its course through Hex's tubing, at the end of ''Discworld/InterestingTimes'', thus causing Rincewind to be teleported to Fourecks rather than back to UU. If not for that one ant, the faculty wouldn't have had any reason to visit the office where the portal to Mono Island could be found, in the first place.
** FridgeBrilliance meets ContinuityNod: When fleeing from the police in Bugarup, Rincewind is dismayed and amazed by how the pursuing officers stay on his tail. Aside from a very brief sojourn in ''Interesting Times'', Rincewind hasn't been in Ankh-Morpork since the events of ''Sourcery'', so has completely missed the rebirth of his home city's Watch in the wake of ''Guards Guards!''. He only remembers how lazy and fearful the Watch ''used'' to be, and is probably quite astonished to see what's become of them once he gets home at last.
** FridgeLogic: The god of evolution mentions having had believers at some point, as well as experimenting on a cow he wanted to make more inflammable. If so, how does he not recognise the wizards as humans or, indeed, not know the most popular way of producing new generations, or even about different sexes? What sort of believers (or cows) did he have?
* HilariousInHindsight: Upon learning about portals, Ponder's first idea is to set them up for [[VideoGame/{{Portal}} infinite falling]].