For an emerging travel-booking site to be successful, it needs an edge that established brands like Expedia, Orbitz, and Kayak don't have. So the next generation of sites are finding their niche by borrowing search and display elements from already-popular Web-based businesses. Below is a list of new travel startups aiming to be the Pinterest, eBay, and Tinder of travel booking.

1. Pintrips

This Pinterest-style booking site makes the most out of the visual Web by allowing travelers to pin together flight results from different booking sites. PinTrips makes it easy to quickly compare prices and routes without having to navigate between several different websites.

2. Flightfox

For business travelers who want a human element when booking their corporate or group travel, FlightFox relies on its network of travel experts to create custom travel plans based on a customer's specific needs, including groups and multi-city flights. This online marketplace approach to nailing just the right itinerary is similar to the way graphic design site 99Designs assigns its thousands of design projects.

3. FareScout

One of the most frustrating aspects of booking a flight online is finding that prices have dropped shortly after you've locked in a fare. The FareScout app harnesses the data that airlines have collected to predict price fluctuations. The way the app alerts its users to either wait or buy a flight is reminiscent of Tinder's "hot or not" dating feature.

4. FlyinAway

Currently in beta and based on e-commerce models popularized by eBay and Groupon, FlyingAway turns booking travel into a giant online auction. Travelers search for flights and bid on the lowest fare, but the fare is only activated once enough travelers express interest in the same itinerary.

5. Google Flight Search

To power Google Flight Search, the search giant acquired ITA Software, the company behind the search and pricing technology used by Orbitz, Kayak, American Airlines, United, and several others. Google has also incorporated Google Maps into travel booking, allowing users to change destinations on the map and instantly see how flight prices change.

According to Google chairman Eric Schmidt, the long-term vision for Google Flight Search is the ability to cross-reference flight itineraries so that travelers can simply search for "flights to warm destinations in December where I can snorkel" and get a list of viable results.