Aggregators like Expedia have made us lazy -- and we may be missing out on the best deals. From a report on Backchannel: Most of us rely on metasearch engines, like Priceline, Expedia, or Travelocity, which typically use dozens (sometimes as many as 200) of online travel agents, called OTAs, and aggregators to find the best deals. (A metasearch engine and an aggregator are interchangeable terms -- they both scour other sites and compile data under one roof. An OTA is an actual travel agency that actually does the booking and is the lone site responsible for everything you buy through them.) We rely on these sites because we assume they have the secret sauce -- the most powerful search engines, tweaked by superstar programmers armed with the most sophisticated algorithms -- to guide us to the cheapest options. With a single search, you can feel assured that you are paying a rock bottom price. Over time, however, the convention has flipped. As competition among the sites heated up, the hard-to-believe cheap fares required some filtering. A too-good-to-be-true fare ($99 to Europe from California) usually came with a catch (the $400, indirect, ticket home). And as the business models that on which these aggregators rely are getting tighter, the deals are getting worse. How can you be certain you're getting the lowest quote? The short answer is, you can't.