Where Bill Gates is investing his money?

Bill Gates is best known for his Microsoft billions and the great philanthropic works that have followed. But something interesting has happened recently, and perhaps notably with this year’s Forbes 400 number-crunching, which puts him on our list up $6 billion with a total $66 billion to his name.

Gates’s net worth is now stunningly unrelated to the stock performance of the company he co-founded thirty-seven years ago.

Because of regular stock sales, Microsoft today makes up just one-fifth of Gates’s assets. At the time of last year’s Forbes 400, it was a quarter. The large remainder of his wealth is tied up in an investment entity called Cascade Investment LLC, which is managed out of Kirkland, Washington, a quick drive (with no traffic) from Microsoft’s Bellevue headquarters.

We don’t know much about Cascade except its largest investment positions, and in those, there is some insight about how America’s richest man is placing bets. And perhaps somewhat surprisingly, the king of tech favors more stodgy Warren Buffet-like deals for returns, or at least asset diversification.

This year, for example, Gates gobbled up shares of Republic Services, which operates 334 trash collection companies, 191 active landfills and 74 recycling facilities. Gates has for a while been a large shareholder in Republic Services, but this year increased his stake by 16% as the stock edged up just 3%, barely beating the even more paltry gains of rival Waste Management. Gates now holds roughly $2.2 billion worth of Republic Services stock.

He also upped his stake of auto-dealer network AutoNation by 17%, taking his total stake to a value of $680 million. AutoNation owns and operates 258 new auto franchises, mostly in the Southeast. In contrast to Republic Services, AutoNation’s stock has done nicely this year, increasing 13% as Gates was buying up shares. Another chunk of Gates’s wealth is in cleaning supply outfit Ecolab. His stake here hasn’t changed much over the past year, but is one of his largest known-investments worth $1.8 billion.

All three of these picks trade at what appear to be reasonable values, around 14 times forward earnings for AutoNation and Republic Services. These aren’t screaming deals, but nor are they pricey high-flyers. Amazingly though, Microsoft is more of a deal than these old-industry picks. The software firm Bill built is trading at nine times future earnings. That’s a value play.

Cascade also takes an active role in some of its largest investment. The head of Cascade since 1994, Michael Larson, is a director at several of the companies he has invested in on behalf of Gates, including Republic Services, Autonation, Group Televisa and Ecolab. He also chairs the Board of Trustees for the Western Asset/Claymore Inflation-Linked Securities & Income Fund, another long-time Gates investment.