London's mayor Boris Johnson recently pledged to turn his city into "the electric capital of Europe." Making good on that promise, Hertz has rolled out several options for visitors who want a green way to get around. Electric cars can be rented at several sites throughout the city (bonus: The cars are exempt from London's notorious "congestion charge") and can be recharged at any of 16 stations. The cars reportedly have a range of more than 90 miles.
If your clients are looking for a fresh-air option, they can also rent electric bikes at Hertz's Marble Arch branch for £20 (that's about $32) for the day. Every rental comes with full training, a lock, optional helmet and a copy of the AA Leisure Guide to London with suggested bike rides around the city.