Programming skills, sound business acumen, and a little bit of luck can make you a lot of money in the tech industry. For Valve boss Gabe Newell, these attributes have made him not just rich, but filthy, stinking rich. According to Forbes' most recent 400 richest people in America list, Gaben has an estimated net worth of $5.5 billion.

Anyone looking to become one the 400 richest individuals in the US now needs to boast a minimum net worth of $2 billion, up nearly 18% compared to the $1.8 billion required to make last year's list.

That barrier for entry is no problem for Valve's co-founder and president, who is thought to own just over half the company. His bulging bank account puts him in the number 97 spot. As the rankings are rounded up to the nearest hundred million, Newell shares his position with nine other people, including Wal-Mart heiress Ann Walton Kroenke.

While Valve's initial success came from gaming endeavors such as Half-Life and Portal, it's the company's Steam platform that has helped push Newell's wealth into the stratosphere. Explaining the digital store, Forbes writes: "Some liken it to the iTunes of videogames. Steam sells game licenses to 125 million users of its own and other developers' titles and collects a percentage of the sales." The continuing success of the Counter-Strike games and DOTA 2 has no doubt added to Newell's net worth, too.

The downside to this, of course, is that all the money Valve is making leaves little incentive to put out new games. Sadly, we're unlikely to see third entries in the Team Fortress, Portal, Left 4 Dead, and Half-Life series any time soon, if at all.