Steam founder Gabe Newell is worth US$5.5 billion according to Forbes.

In its latest roundup of the 400 wealthiest people in America, Forbes ranked Newell the 97th richest person in America, tied with a Wal-Mart heiress and several Texan oil barons.

Forbes said the price of admission was even higher for this year’s list, with the minimum net worth now at US$2 billion, up from US$1.7 billion last year. That is a jump of 18 percent in only a year.

In its write-up on Newell, Forbes mentioned his humble beginnings as a developer, but highlighted that his worth came from his ownership of Steam.

"Some liken it to the iTunes of video games. Steam sells game licenses to 125 million users of its own and other developers' titles and collects a percentage of the sales," Forbes said.

Steam is not a publicly traded company, and so does not have to disclose its financials. However, looking at Newell’s US$5.5 billion piggy bank, it is safe to assume the company is ticking along nicely. It is estimated Newell owns just over half of Steam.