Marketing expert Dave Hecker of Denver has come up with a novel way for businesses to advertise: rolling billboards.

The 29-year-old's company, Chumba Media, charges $35 an hour plus a $300 production fee to print the ad, and he has“brand ambassadors”push them around the bustling 16th Street Mall, an outdoor walking mall in downtown Denver, during busy times. He tells reporter Amy DiPierro of the website BusinessDen.com that it offers businesses of any size an affordable way to advertise, and it allows them to choose specific times and locations to deliver their message.

“When we're walking around, we have numerous, dozens of people talking to us,”Hecker tells the news site.