TourBus is a WebRing like organisation of wikis and digital gardens. This is an old system (20+ years), which is currently under renovation under the new rule. MeatballWiki serves as a central hub for the system.
Who is on the bus? You are, if you want to be. Anyone following a bus link is "on the bus".
When do they go to the bus stops? Whenever they get bored with the wiki they're at.
What do they do there? Follow the links to the next stop.
Is the bus even active? In as much as the wikis involved have not died, and their bus stops have not been vandalized, yes.
Outdated, a lot of information should be deleted, but some should be updated: