A Profitable Alternative to the Bicycle Watch out, bikers and bladers. The elliptical trainer has zipped out of the gym and onto the streets.

As fitness equipment goes, the world's first elliptical bicycle is pretty darned impressive. It's got the sleek curves of a high-end road bike, the clean lines of a Razor scooter, a pair of shiny carbon-fiber elliptical pedals, a smooth hub-and-crank stride mechanism and a steering column that collapses for easy storage. Plus, it's not awkward using it (think Smith machine): Just hop on and start stepping.

"We knew we were onto something when we showed a prototype and people were telling us to make that exact model," says Bryan Pate, one of the ElliptiGoinventors. It was Pate's bad knees that started the whole thing rolling: In 2005, he had to stop running and found that neither elliptical trainers nor cycling were satisfying alternatives. "I wanted something that would emulate the feel of running outdoors without beating up my knees," Pate says. It didn't exist, so he figured he'd have to create it himself.

He called his friend Brent Teal, a fellow Ironman athlete and mechanical engineer, who set up shop in the garage and cobbled together the first prototype out of chromoly steel, modified roller blade wheels, wooden boards and old triathlon bike parts.