In  Haverhill, MA, a State Trooper was running radar in a perfect
spot to watch for speeders, but wasn't getting any.  He later discovered the problem. 
A 12 year old boy was standing a ways up the road with a hand-painted sign which
read 'RADAR TRAP AHEAD!' The officer then found a young accomplice down the road
with a sign reading, 'TIPS' and a bucket full of money. (Beats a lemonade stand!)

A motorist was mailed a picture of his car speeding through an automated
radar post in Bradford, MA.  A $40.00 speeding ticket was included.
To be cute, he sent the police department a picture of  $40.00.  The
police responded with another mailed photo of handcuffs.