Bielefeld conspiracy theory
1. Bielefeld conspiracy theory
Originating from German USENET, there is a joke conspiracy theory that the German city Bielefeld doesn't exist. It seems to be particularly popular around university students – Bielefeld is a university city – who see it as a kind of inside joke. It originates from some guy who accidentally said that it doesn't exist.
The people believing in this theory are arguably very annoying, albeit sometimes funny.