Uni prank - the top half of a sedan - on a raft - painted and with flashing lights to look like a police car, floating down the river ....

Once, the Qld Uni guys set up on a traffic island in a roundabout, complete sandy desert island, complete with beach chair, palm tree and sunbaking person ....

Best though was walking across the Qld Uni quadrangle, looking up at the tower clock to see that someone had placed a mickey mouse poster, and fitted white gloved hands.... took security 2 days to figure out how to get it down - I know of the guys who rappelled down to put it there... :)