Google has made a lot of acquisitions right from the beginning. The most popular of google's products are acquired by google from some other companies. For e.g youtube, picasa are acquired companies.
Recently google acquired on2 technologies who developed the famous compression codec VP6 and VP7. They also developed many codecs. Google acquired it for $106.5 million.

For detailed report visit

To see the list of acquisitions done by google from the beginning visit
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