Buried in the first quarter earnings report from Microsoft is an astounding fact. For the first time that I can remember, Microsoft closed the quarter with less cash than Apple. Cash, cash equivalents and short-term investments for Microsoft add up to $20.7 billion. Apple, meanwhile, closed the quarter with $24.5 billion.

There are a lot of things that explain this. Microsoft is still a cash machine in Windows and Office, but it has been pouring its money in recent years into shareholder dividends, stock buybacks, and acquisitions. Apple, meanwhile, hasn’t been as aggressive on those fronts. Microsoft doesn’t even have enough cash to buy Yahoo! outright; it would likely have to finance an acquisition with some debt.

Steve Jobs, chief executive of Apple, said yesterday, “The economic downturn may present extraordinary opportunities to companies that have cash. Cash is king. We are very comfortable with cash in bank and it is not burning a hole in our pocket.”

I never thought I would see this day.