Roamin' Holiday

What urban hipster hasn't dreamed of zipping around traffic on a sleek Vespa or WWII paratrooper scooter à la Gregory Peck? The trouble is, most mopeds and motorized scooters are powered with cheap two-stroke engines, which are fuel inefficient and heavily polluting (as well as noisy and rather unreliable). As a result, European cities like Granada, Spain, that have banned cars in central areas still suffer from smog. "Surprisingly, a scooter—especially one using the exceedingly dirty two-stroke technology—puts out dramatically more pollution per mile than one of today's clean burning cars," says Danielle Fugere, global warming program director for Bluewater Network. "Since small engines can be such big polluters, we must move to cleaner technology."

Four-stroke gas engines like that on the Vespa GTS ($5,799, top speed 75 mph; www.vespausa.com, 800-631-1101) can be an improvement and typically get 65-70 miles per gallon, meaning consumers can expect to spend about $6 in gas for two weeks of typical use. Further, Piaggio, makers of Vespas, is currently in the research and development stage of hybrid gas-electric scooters in Milan, in collaboration with the Italian government. Christine Gifford, manager of a Vespa dealership in Ridgefield, Conn., says scooters in general are surging in popularity due to high gas prices.

Product Picks: For years, California's ZAP! has led the field of electric scooters. The latest model, Zappy3, boasts three wheels for stability and costs pennies to charge for a 12-mile ride with a top speed of 12 mph ($499; batteries, $60; www.zapworld.com, 800-251-4555).

Well-known for those thin, push-powered scooters now plying sidewalks everywhere, Razor also offers an electric Chopper model that gives kids 12 and older the chance to cruise up to 15 mph on their own pollution-free "Harley" ($229; 10 miles per charge or "mpc"; www.razor.com, 866-467-2967). Though the scooters go slow, children should wear helmets for safety.

For a ride more akin to traditional mopeds, check out the eGo Cycle 2. The Massachusetts company's cycles aren't cheap, but they are clean and efficient, and can reach a speed of 24 mph ($1,199 and up; 20-25 mpc; www.egovehicles.com, 800-979-4346).

If you need even more speed, consider the electric Z20 from EVTAmerica ($1,999; 30-45 mpc; www.evtamerica.com, 305-480-6007). The sleek, moped-style design can approach 45 mph. An attractive retro-looking model is also available for $1,999.

If you need speed for two, E-max might be for you. Starting at $2,050, the German-made, two-seat electric scooter can reach a top speed of 28 mph (30 mpc; www.e-max-scooter.com). Among electric options, newer technologies have their flaws: Segway's Personal Transporter was recalled in September due to the risk of riders falling off.

For traditionalists and kids 5 and older, you can't go wrong with good old-fashioned "push power," from the non-electric Razor to designs by Xootr (starting at $179; www.xootr.com, 800-816-2724).