94027 -- Atherton, Calif.
One of the few most expensive ZIP codes not located near New York or Los Angeles., 94027 doesn't need a big city to bolster its appeal to the wealthy. Atherton, Calif., is at the heart of Silicon Valley.
Though no large tech company is headquartered there, Atherton is home to several industry notables. It's most prominent? That's probably Eric Schmidt, executive chairman and former CEO of Google. Add to the list former eBay CEO and California gubernatorial candidate Meg Whitman and financial big wig Charles R. Schwab.
Despite its list of high-profile residents and a median home price of $4 million, Atherton prides itself on being a simple, heavily wooded community (its original name was Fair Oaks) [source: Forbes, City of Atherton]. The town even formed a tree committee in 1989 to help protect its original namesake resource.