In what's billed as a first for the United States, Denver has instituted a citywide bike-sharing program, dubbed B-cycle, that makes 500 new shiny red Trek bicycles available at 40 stations throughout the city (at places like the Colorado Convention Center and the Denver Art Museum). Users can purchase a 24-hour membership for $5 at any station, take a bike, pedal around town and then simply return it to the nearest station. Users also can sign up for seven-day ($20), 30-day ($30) or annual memberships ($65) online (usage fees also apply). The program already has made inroads in more than 50 cities in Europe and Asia. For more details, visit denver.bcycle.com.