"Paris Buys Citizens Bikes" (Rental Program)

Paris, France has adopted an innovative, yet wonderfully simple, approach to reducing congestion and greenhouse-gas emissions in city limits. It's buying its citizens bikes.

22,000 of them.

The program, paid for by an outdoor advertiser in exchange for the exclusive use of 1,628 urban billboards, allows people to rent the large gray bicycles at a rate 1 euro ($1.38) a day; a week pass costs 5 euros ($6.90) and a yearly subscription, 29 euros ($40). The fee gets you a maximum of 30 minutes' bike use at a time; ride for longer in one trip, and there's a small incremental fee. The time limit is intended to keep the bikes in circulation; however, you can use the program as many times as you like within the period for which you've bought a pass.

The program is part of an effort by Paris mayor Bertrand Delanoë, who is aiming to reduce car traffic in the city by 40 percent by 2020. The number of bikes in Paris has increased by 50 percent in the last six years; thanks to the principle of critical mass (the more bikers there are, the safer they are), the number of accidents has stayed roughly the same.

Yellow-bike and similar programs have met with mixed success in the US. Perhaps what the Paris experiment demonstrates is that it takes a massive show of will (and prioritization of dollars) to create the critical mass we need to revolutionize our transportation system.