In the 1970s I had a mate who ran a mechanics business on the Hume Highway in Western Sydney. He was given a hovercraft as a debt payment back when they were still experimental.
He went to DCA, Marine and DMR to find who registered such things and no one wanted to accept responsibility. So being resourceful he "drove" the craft along the highway only to be booked for driving an unregistered vehicle. Responsibility proved??
The local cops spent the next weeks trying to get the ticket back.I bet there were a few hard words in Highway Patrol headquarters over that one.
Wunwing