Groupon offers local discounts if enough people 'buy in'
The way it works is that Groupon negotiates a steep discount -- generally about 50% off -- with a local merchant. But to get the deal, a certain number of people have to "buy in."
Groupon = group +coupon.
Once that threshold has been met, the discount is set and everyone who buys gets the deal. Generally, each offer is available for about 24 hours, which you can redeem later. Oftentimes the discount will sell out before the timer expires.
I belong to Groupon.com in Los Angeles and have seen discounts for spas, restaurants, events, and even ferry rides. Some of the discounts seem like great deals to me, others are so so. It really depends on how you spend your money. Groupon also features deals for theater tickets, classes, bars, museums and gyms.
Check if Groupon.com is in a city near you.