Just days after reports that Google and Facebook were interested in partnering with, and possibly buying VoIP company Skype, Microsoft announced that it was buying the company for $8.56 billion in cash.

Last year, Skype had revenue of $860 million on which it posted an operating profit of $264 million. However, overall it made a small loss of $7 million, and had long-term debt of $686 million. This is the second time Skype has been bought out; after being started in 2003, it was purchased by eBay in 2005 for $3.1 billion. EBay then sold the majority of its stake in 2009 to a private investment group for $1.2 billion less than it paid.

The purchase was Microsoft’s biggest ever, surpassing even the $6 billion acquisition of advertising firm aQuantive in 2007. That alone makes it surprising; the company’s track record with large purchases is decidedly mixed. Danger, the exciting mobile technology company that produced the Hiptop, better known as the T-Mobile Sidekick line, was purchased for an estimated $500 million in 2008; the result of that purchase was the disastrous KIN phone and a complete failure to integrate the bought-in talent. The aQuantive purchase too had mixed outcomes, with Redmond unable to find a role for the Razorfish division before eventually selling it off in 2009; Microsoft continues to be unable to make a profit from online advertising.