The remnant of an apparent joyride on the snow-covered slopes of Dollar Mountain has left Ketchum and Sun Valley police a bit perplexed. A Toyota Land Cruiser registered to a Sun Valley man was mysteriously left abandoned part way up the ski mountain late Sunday night, seemingly after it veered off the groomed terrain into unpacked snow. The vehicle was discovered at 12:30 a.m. Monday morning by the operator of a Sun Valley Resort grooming machine, said Mike Crawford, assistant Sun Valley police chief. Shortly after police went to the scene to investigate, the owner of the SUV called from Ketchum to report that it was stolen, Crawford said. Ketchum police are investigating the incident.