David Crane of Crane Builders in Nashville, Tenn., found himself faced with laws that prohibit job signs in the area's two ritziest neighborhoods, Belle Mead and Forest Hills. So he had magnetic signs made for seven people in his company whose cars populate those neighborhoods. (One employee with a beat-up pickup doesn't get a sign.)

"When we looked at our marketing, here are the two richest sections, and we have no signs to tell people we're the ones doing the jobs," he says.

This solution is "a good way to get our name into the neighborhoods where normally you couldn't. There are tons of big construction jobs in these neighborhoods with nobody's sign on them." To stand out from trucks with painted-on signs, he had oval signs made, using his eye-catching crane logo.