Once known as the world's richest company, Microsoft (NASDAQ:MSFT) has resorted to the unthinkable: agreeing to sell $3.75 billion in corporate bonds. That's right; this one-time cash champion -- so flush that it paid investors a one-time $3 per-share dividend in 2004 -- is taking on debt.

Interestingly, Mr. Softy isn't alone. Cisco (NASDAQ:CSCO) recently increased its leverage, joining stalwarts Oracle (NASDAQ:ORCL) and IBM -- other tech-heavies that have dipped their wallets in the debt-market pool.

Their timing is interesting. Most firms have used equity to raise capital after the credit markets froze during the global financial crisis. Yet now there are signs that the market is thawing. The TED spread is narrowing, and like stocks, high-yield bonds are recovering from an awful performance in 2008. Microsoft's entry into the debt market could further smooth volatility by boosting confidence.

Meet the new Oracle?
For its part, AAA-rated Microsoft is likely to raise all $3.75 billion at very attractive rates, which could be a boon for investors if executives find ways to deploy that bounty at high rates of return.

In other words, Microsoft needs to position itself to be more like Oracle.

Few in the industry can match CEO Larry Ellison's record of using leverage to his advantage. Rather than spend precious equity, the database king typically resorts to its flush balance sheet and rich cash flows to buy rivals. That's been the case with deals for PeopleSoft, BEA, and Siebel in the past, and it will be again when Oracle commits $7.4 billion to purchase Sun Microsystems.

History calls this a smart strategy: Oracle's returns on capital have remained steady -- between 16.7% and 17.8% -- as growth has soared since its acquisition spree began in 2004.

Here's your shopping list, Mr. Softy
Where would Microsoft CEO Steve Ballmer use his new corporate charge card to go shopping? The obvious choices would be business software partner SAP, which would benefit from having tighter ties to Microsoft's SQL Server database, and Yahoo! (NASDAQ:YHOO), whose search business has already been a target of Ballmer's teasing.

Either deal would make sense for Microsoft's corporate customers -- partnership talks with SAP stretch back years -- but I wonder if Mr. Softy's fresh dollop of capital wouldn't be better spent building its consumer-facing business. Here are three of my best ideas:

Netflix (NASDAQ:NFLX). An obvious choice, insofar as CEO Reed Hastings sits on Microsoft's board and the two companies have cooperated to deliver movies through the Xbox 360. Plus, as a retail partner, Netflix would be ideal -- drop off your videos at the Microsoft entertainment center in exchange for your favorite Xbox games.

Twitter and Facebook. Any serious run at Google (NASDAQ:GOOG) would necessarily include social search in some form. Microsoft already has $240 million committed to Facebook, whose 200 million users gush data daily, and Twitter is apparently talking with everyone except for Google. That's a huge opportunity.

VMware (NYSE:VMW). Remember the old Microsoft mantra: "Embrace and extend?" When it comes to cloud computing, data centers are what you embrace, and virtualization -- the practice of transforming one server into the equivalent of many, dramatically boosting productivity in the process -- is what you extend. VMware is the market leader in virtualization, but Microsoft, through its Hyper-V product, wants a piece of the pie. Why not buy whole the pie instead?

Microsoft already has close to $24 billion in excess cash. Soon, it'll have another $3.75 billion more. That's one heck of a charge card, Ballmer. Time to go shopping.

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