A police officer had a perfect hiding place for watching for speeders along a well traveled stretch of highway. The location, at a bend in the road, allowed him to hide his car out of sight of oncoming traffic while setting up his radar to nab any speeders who passed by. He had used this location successfully a number of times, especially on holidays, and decided to use it again one Labor Day weekend.

The officer arrived at his hiding place and set himself up, settling down to wait for the first speeders to appear. After a half hour or so the officer hadn't seen anybody speeding. In fact most of the cars that passed him were traveling exactly at the speed limit, and some of the passengers in the passing cars were even smiling and waving at him. He couldn't believe this was happening since his hiding place was so well concealed.

Finally, after realizing that virtually all the passing cars knew he was there, the officer decided that something was wrong and went to investigate. He got out of his car and walked up the road a short distance. About 100 yards before his hiding place the officer found the problem: a 10 year old boy was standing on the side of the road with a huge hand painted sign which said "RADAR TRAP AHEAD." A little more investigative work led the officer to the boy's accomplice, another boy about 100 yards beyond the radar trap with a sign reading "TIPS" and a bucket at his feet, full of change.