Caviar is one of the first things that comes to mind when people ponder "exotic" foods. But Russian sturgeon in the Caspian Sea, the source of the world's most revered caviar, has been overfished and the sea has been polluted. Imported wild-caught caviar is also heavy with unhealthy mercury and polychlorinated biphenyls (PCBs). Does that mean you should skip caviar, and give up all its associations with the good life? Nope. When you want to celebrate and occasion or a vacation with caviar, opt for caviar from farmed sturgeon in the United States. There are several outstanding producers in California, such as San Francisco-based Tsar Nicoulai, so consider sampling caviar on your next visit to the City by the Bay.