Bonds.
Microsoft Announces Debt Offering
Offering is part of $6 billion debt authorization by board of directors in September 2008.
REDMOND, Wash. Â May 11, 2009 Â Microsoft Corp. today announced the pricing of its offering of $3.75 billion of senior unsecured notes. The notes consist of the following tranches:
 $2 billion of 2.95 percent notes due June 1, 2014
 $1 billion of 4.20 percent notes due June 1, 2019
 $750 million of 5.20 percent notes due June 1, 2039
Microsoft intends to use the net proceeds from the offering for general corporate purposes, which may include funding for working capital, capital expenditures, repurchases of stock and acquisitions. The offering is expected to close on May 18, 2009.
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I guess the "free money" from the stock market wasn't enough for them to keep up with their spending, or something. Whether it was related to XBox or their phone(s) or Bing or MSNBC or ..., I can't say.
FWIW.
Cheers,
Scott.