In Australia they have mobile speed cameras in vans. Anyways some cheeky lads pulled over and started asking the operator if they could have a look as they were engineering students at the uni and were curious about the hardware. While they were talking to the operator one of the lads took the back numberplate off the van, they quickly went and threw the plate on another car and then sped past the camera, went around the block and did it again about half a dozen times.

Iirc they were never caught and it made national news. Now the vans have an array of 4k cameras on them.