A man who had to learn to walk again after he broke his back in a car accident has raised $30,000 by riding across the United States -- on a UNICYCLE.Peter Frank, 21, rode a hand-modified unicycle and covered 2,400 miles (3,800 km) across eight states in just three-and-a-half months.He set off on the mammoth journey, from Appleton, Wisconsin, to Phoenix, Arizona, to raise cash for Beacon House, the charity that helped him after his car accident.Peter, an avid unicyclist from the age of 11, was hospitalised after a car ran him over aged 14.