Driving into the city, I often see bicyclists riding to work; some of them zip along even going uphill for long stretches (the ones with muscular calves that look like they belong on a race horse). You can always spot the novices, who seem to be having a grand old time, all smiling and rosy-cheeked, until they encounter that impossible hill. Nothing like a nice uphill struggle to take the wind out of your sails when you're trying out a new, healtheir lifestyle. I tend to avoid uphill rides altogether, having no aspirations whatsoever of being an athletic rider. So I've often thought it would be nice to have a bike that helps you only when you need it, giving your pedaling just a little extra push.

This Urban Terrain electric bicycle has a torque-sensing motor that provides 100% assistance on hills and 50% on flat terrain, for up to 30 miles on a single charge, and at a maximum powered speed of 18 mph. The aluminum frame is lightweight (well, if you consider 49.5 pounds lightweight) and foldable, so would work well for taking on trains, or commuting all the way to the office, where you can carry it up the stairs, remove the 9-pound battery and charge it up for your ride home (5 hours for a full charge). This e-Power bike, available from Gaiam for $1,199, is equipped with Shimano Axus 6-speed derailleur gears, thumb-shift gear change, alloy wheels, and front and rear V-type brakes.