Dwellable, launched a year ago by Adam Doppelt (a co-founder of Urbanspoon, since acquired by IAC) and Rob Currie, is a rental search site that includes all listings for free, providing access to more than 50, 000 vacation rental listings across the United States in markets including Cape Cod, Colorado, Florida, Hawaii, Hilton Head, Lake Tahoe, the Outer Banks and San Diego.
When personal data is easily swapped and shared on the network, a couple of keystrokes gets you, say, a United reservation, frequent-flier number included, plus the kind of rental car you like and your hotel reservation--even listings of the movies or restaurants that have opened since your last visit.