TerraCabsLookin’ for a free ride this summer? Meet the TerraCab.

This curious-looking fleet of teardrop-shaped vehicles could soon hit Seattle streets in search of ped-weary passengers. But they don’t plan to peddle greenhouse gases. TerraCabs are emission-free — powered solely by pedalers, aside from a small rechargeable battery for headlights and hill-assistance.

They are also intended to be free-free, as in cost you not a dime. How is this possible? Say their PR folks, “forward-thinking companies sponsor them,” which means they are painted with ads and drivers may hand out samples or coupons as you hop on. That’s the idea, anyway. Unfortunately, they don’t have the corporate sponsorship necessary to put any TerraCabs on the, er, terra in time for the planned Earth Day launch.

Once they do, however (tell all your corporate-flack friends!), they plan to be up and running (er, pedaling) Wednesdays through Sundays — with routes in Belltown, Pioneer Square, Sodo, and along the waterfront — all summer.

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And for those of you who need free rides even more than some, consider conditioning your calves: TerraCab is hiring personalities with pedal-powered stamina.