Cops routinely use cherry pickers on RT50 heading into OC MD on holiday weekends. They look as if they are maintaining billboards.
A women I work with was pulled over by a cop who stood in the highway. She yelled at him for scaring the crap out of her when he jumped into her path and he let her go
There was an article in Car&Driver a month or so ago about Ohio highway patrol officers in airplanes. They actually made it sound more "fair" in that they would watch driving habits for a few miles before deciding who to pull over.