This will never work:

Jarry Slaughter, an Oklahoma Transportation Authority engineer, has posted speed limit signs of 17 mph at three toll plazas that are under construction.

He said he can't scientifically measure the effectiveness of the unusual speed limit, but he's convinced it works.

Growing up in Virginia Beach, we had a 13 1/2 mph speed limit sign posted in a local shopping center parking lot. Legend has it, it was one of the most stolen signs in the city.