Looking around for the richest municipality in America, I stumbled upon one candidate: the tiny town of Bradbury, CA, which sounds like it ought to have its own soap opera: "Dallas" as directed by David Lynch.
Bradbury, population 1000+ is mostly two gated communities in Southern California's San Gabriel Valley, in the foothills beneath Mount Baldy.
Bill Bishop's 2008 book The Big Sort documented the trend that Americans are sorting themselves out geographically by social class. But Bradbury seems to consist of people who are filthy rich (one Bradbury home is on sale for $79 million), like riding horses, and haven't been rubbed smooth by modern America's class-formation process: drag racers, televangelists, civil rights entrepreneurs, hamburger heiresses, Saudi princes, Dominican sluggers of uncertain age, racehorse trainers, Chinese exiles, jockeys, Caltech geniuses, and faith healers.
Here's an augmented version of Wikipedia's list of prominent Bradburyians:
- Lynsi Snyder Seawell Martinez Torres, owner of and heiress to In-N-Out Burger, youngest American female billionaire, and drag-racing aficionado
- Yang Rong, billionaire Chinese automotive tycoon, formerly third richest businessman in China before his hasty departure 
- Peter Popoff, televangelist and faith healer exposed by James Randi, now focusing on African American market
- Zhang Jizhong, prominent Chinese film producer
- Ahmed bin Salman bin Abdulaziz Al Saud (deceased), Saudi Arabian prince, racehorse owner, accused of ties to 9/11
- Babe Dahlgren (deceased), baseball player, replaced Lou Gehrig after 2,130 straight games at first base for the Yankees
- Mickey Thompson (deceased), drag race driver, murdered at his estate in Bradbury in 1988; 19 years later his business partner was convicted
Stan Williams is the winner of the 2000 Feynman Prize in Nanotechnology. I think Richard Feynman would have liked this place.