BOOKING LAST MINUTE TRAVEL
WINNER: None

There are three well-known players in this arena: LastMinute.com, 11thHourVacations.com, and LastMinuteTravel.com. In our tests, none delivered a lower last-minute fare 48 hours before departure than online travel agencies or travel search engines.

BOOKING HOTELS IN THE U.S.
WINNER: Hotels.com

WHEN TO USE: Any time you're shopping online for a hotel stay.

WHY WE LIKE IT: Hotels.com offers the best combination of rates and functionality of any site we tested. For instance, we found a marina-view room with breakfast at The Dana on Mission Bay in San Diego for $139 per night, $20 less than on Expedia, Orbitz, Quikbook, or Travelocity—or even the hotel's own site. Sliding toolbars allow you to sort results by price, star ratings, and guest ratings. Hotels.com has a "no change or cancel fees" policy, but it covers only charges levied by the site, not by the properties themselves. One of the most confusing aspects of selecting a hotel is the very subjective star ratings, since each site uses its own criteria. Hotels.com provides ratings based on reviews by the site's "experts" and guest ratings based on customer surveys.

TIP: Hotels.com's Rate Calendar has the best comprehensive pricing comparison six months out.

CAVEAT: The site has offerings worldwide, but Kayak and Asia-Hotels.com have more options for Asian properties.

RUNNER-UP: Orbitz.com
Its booking tools are just as useful as Hotels.com's, but a few times Orbitz posted rates for sold-out rooms.

BOOKING ON AFFORDABLE LUXURY HOTELS
WINNER: LuxuryLink.com

WHEN TO USE IT: Your dates are flexible and you're looking for posh digs at budget prices.

WHY WE LIKE IT: You don't need to pay a membership fee, and savings can be as high as half off the regular rates. Many travel sites claim to offer discounts on luxury hotels, but we've found that Luxury Link delivers the best values on the greatest array of upscale properties worldwide. In our tests, the winning bids on Luxury Link ranged from $146 to $1,966 below the lowest prices available.

CAVEAT: Bidding takes time and patience.

TIP: Rather than purchasing a package, bid on a room and then buy the extras (meals, wine, golf) à la carte.