1. Have I got an ab-fab deal for you. Word of so-called secret sales on the Web has spread fast. The idea is to promote an illusion of exclusivity. You must be invited via e-mail to be a member to get deep discounts on items such as lavish vacations and designer clothes. Don't have a friend who is already a member? No problem. Apply to the site directly. Most applicants are granted access within a couple of weeks, and some sites let you in instantly. The veil of secrecy serves another purpose: It allows high-end hotels and fashion icons to unload unsold inventory without sullying their brands in public.
2. But you'll have to act fast. These offers are "flash sales" that typically last one day to one week, giving you little time to mull over a purchase before you commit. Travel deals are available for a limited time, too, but you usually just have to book your trip -- not take it -- within the narrow window.
3. Get stiletto heels at down-to-earth prices. The sites work best to save you the steep prices of luxury goods. At Ideeli.com, for example, you can bag bargains of up to 80% off retail on fashion, home and beauty products. In early March, the site was offering BCBGeneration's Zuton ankle boots, with peep toes and stiletto heels, for $65, down from $139. Other fashionable sites to drool over: EditorsCloset.com, Gilt Groupe, HauteLook.com and RueLala.com.
4. Spend a weekend in Rio or on the Riviera. Private-sale travel sites work best for "more spontaneous people," says Anne Banas, of SmarterTravel.com. Most sites feature only a handful of offers at a time. The exception: JetSetter.com, which offers 15 to 30 deals at once and can save you up to 50% off published rates. In early March, membership in JetSetter.com could have saved you 30% at the four-star Sofitel Sao Paulo Ibirapuera, in Brazil -- $185 a night versus $264. And we've wangled you an invitation. For other travel sales, check out Vacationist.com, SniqueAway.com and TabletHotels.com.
5. Go with the crowd. You can score a big discount with a bunch of strangers via sites such as Groupon and LivingSocial. Sign up and you'll get deals from local restaurants and businesses delivered straight to your in-box. The goal is to get a certain number of people to buy in; once the target is met, everybody gets the deal. And if too few people buy in, no one is charged. (A similar deal is coming soon to Kiplinger.com.) TripAlertz.com puts a travel spin on the Groupon model. The site displays possible deals, and you vote for the ones you want. The trips with the most votes become available for booking. Here's the really cool part: The more people who book the trip, the lower the price.
6. Ignore the countdown clocks. Take your time and make sure you understand what you're buying. Suzy Gershman, author of Where to Buy the Best of Everything, recommends sticking with brands you're familiar with. "Unless you know exactly what size looks right on you, using these sites is like shopping blind," she says. For travel deals, watch out for booking restrictions and blackout dates. And with Groupon and LivingSocial offers, check the fine print for expiration dates and other details.