Though it prohibits us from bench-pressing cars, gravity can't be abolished because it's the best thing for getting water out of the sky and the only thing keeping football stadiums from floating away. Temporarily escape it with today's Groupon: for $40, you get iFly SF Bay's Earn Your Wings package, which includes a training session, flight gear, assistance from a personal instructor, and two flights in iFly SF Bay's gravity-defying vertical wind tunnel, plus a DVD of your session (an $81.95 total value). This Groupon is valid Monday through Friday only. Flyers who are more than six feet tall must weigh less than 250 pounds; those less than six feet must weigh no more than 230 pounds.

IFly's technology mimics the feeling of skydiving without the "human body plummeting toward the earth at 9.8 meters per second" factor; it simulates a dive by suspending you only a few feet off the ground. The tunnel is a safe way to enjoy the thrillcitement and spectaculation of skydiving for people who love the idea of skydiving, but don't like the idea of wearing a cumbersome parachute, falling out of a plane from 18,000 feet in the air, or skydiving.

Two flights in the tunnel—the time equivalent of three tandem skydives—gives you plenty of time to practice your MJ-tribute moonwalk, rid the dust from your gaming cartridge, or pop the question to a significant other or a person who you'd like to make your significant other. The DVD lets you relive your tricks and maneuvers for years to come, or until the DVD gets replaced by digital-VHS in 2019. IFly is open to people of any age, so round up your Girl Scout troop, bridge club, or oil refinery and take them flying.

You must schedule ahead. Those with a history of shoulder dislocations should not fly. Your two flights cannot be split between two people; one person must use both.

Reviews

More than 100 Yelpers give iFly SF Bay an average of 4.5 stars; Citysearchers give it a perfect five overall:

• I'm an outdoor skydiver with 18 years and 3,500 jumps under my belt. While there is no experience quite like jumping out a plane, iFly SF Bay provides a totally authentic re-creation of the freefall experience. So authentic in fact that outdoor skydivers use facilities like this to train their flying skills for competition. – bradstyle, Citysearch
• I am hooked. This is really a blast... The staff are very helpful and really work hard...On my second visit I was so proud to have improved to the point that I could fly where ever I wanted and even flew to the exit under my own power. – chuckeroonie, Citysearch
• I have over 1300 skydives and I truly love iFlySFBay. I just can't get enough. I've taken many non-skydivers and they to [sic] have loved it -- from 3 yrs old to 60+, they all had a great time. – Aerialsoul, Citysearch