In its annual listings of the global individual wealth, Forbes magazine also released the youngest billionaires in the U.S. The top youngest billionaires in the United States are evidence that enormous fortunes can be created in far less than a lifetime.

All of them are under 40. The youngest, Dustin Moskovitz, is just eight days younger than his Facebook co-founder Mark Zuckerberg (both are 26). The oldest in this group, Google Inc. co-founder Sergey Brin (age 37), is also the group's richest, boasting a net worth of $19.8 billion. All ages are as of March 28, 2011.

Start slideshow to view a gallery of the youngest billionaires in the U.S. in order of rank: