What: Booking site for group travel, small or large.
Why: Useful if you have several people taking a trip together, all needing flights, hotels, cars or sightseeing activities.
How: Search for airlines, hotel rooms and cars by number of travelers. Also lets you narrow down activities for a destination based on interests and who is in your group.
What: Extremely quick airline search site that draws information from 600 airlines around the world.
Why: Major benefit is that it checks foreign airlines, even discounters. You may find flights and routes you didn't know were available.
How: Very simple. Put in destination and dates. You can sign up for e-mails about deals from your home airport.
What: New "Best Days to Fly" calendar is excellent for booking holiday travel and finding the cheapest days to fly.
Why: Lots of Web sites have a variation of this, but this is one of the clearest, and it's easy to use.
How: Put in your departure and arrival city and check the best prices. You can put in a "name your own price" bid, too.
What: Site for planning around-the-world flights.
Why: On many itineraries that take you to distant lands, it's actually cheaper to fly around the world rather than point to point. Also, the site gives you prices on RTW (round-the-world) flights with at least four stops.
How: Price itineraries by clicking your route on a map or clicking on various cities. You'll also get suggestions for similar routes that give you more for your money.