Reverse skiing up a mountain is only possible during full moons on the summer equinox, which is why Rube Goldberg invented ski lifts. Rise to the top with today's Groupon: for $150, you get a season pass to Mt. Crescent Ski Area in Crescent, Iowa (a $299 value).

Thanks to 20 hard-working snow machines, skiers and snowboarders of all levels can zip down runs reaching up to 2,000 feet at this western Iowa resort. Although gravity will pull patrons inexorably toward the bottom of the slopes, two chairlifts return as many as 3,600 snow surfers to the top each hour, where they can take in views of the park's 50 acres, test their mettle on the challenging Double Trouble Chute, or make a snow-sculpted diorama of the entire cast of Happy Days . Afterwards, skiers can warm their toes in the newly renovated two-story lodge and replenish their bodies with a drink from the Mountain Cafe & Bar. Guests can also rent skis and snowboards for $25 or conquer the slopes on an office chair.