Between 2011 and 2014, Microsoft acquired 29 companies, including some big bets like Skype for $8.5 billion, Nokia for $7.2 billion, and Yammer for $1.2 billion. Last year, it made a lot of smaller bets, purchasing 18 companies — and this year is off to a fast start as well with four acquisitions already. Read on for some of the recent acquisitions that have had an impact on Microsoft's IT portfolio.