Design Your Own Discount Getaway

If you've tried booking a vacation online lately, you may have gotten a new whiff of freedom. On travel sites Expedia, Travelocity, and Orbitz, you can mix and match airlines, hotels, car rentals, and even lift tickets or surfing lessons into one customized, money-saving package.

Called dynamic packaging, this feature liberates you from having to pick only deals designed by, say, an airline-owned tour company that insists you use its planes and partner hotels. Expedia pioneered dynamic packaging two years ago and now gets almost 30% of revenue from package buyers. Little wonder Travelocity and Orbitz rolled out packaging engines last year.