This fall, Ripon College in Ripon, Wis., is offering freshmen free mountain bikes, helmets and locks in exchange for a promise not to bring a car to campus. The $300-per-student cost is funded by private donations.

The college's president, David Joyce, says the project was meant to avoid building a parking garage, but its side effects are beneficial: less pollution, more exercise and savings on gas.

The timing was right, Joyce says: "We were either extremely brilliant or extremely lucky."