It’s frightening how many of them look almost uncontroversially realistic. The Outside in favorite (predictably enough) was the ‘Bilderbergularity’:
Billionaire overlords throw in the towel trying to run the planet, escape en masse to low earth orbit. People around the world breath a sigh of relief … before falling onto each other like zombie hordes.
[A Governmentularity / Fungularity mash-up would work well for me.]