Facebook acquired Sofa, an Amsterdam-based software firm that has designed icons (including Mozilla and Nike) and created several pieces of Mac software.

"We’re excited to announce today that Facebook has acquired the Sofa team… We expected to keep working at Sofa forever. But after Facebook first made contact, we were quickly convinced to join forces. The Sofa team will be moving from Amsterdam to Palo Alto in the coming weeks - and we’ll make sure to infuse some of our particular flavor of Dutch culture at Facebook."

Note that Sofa’s products, Kaleidoscope and Versions, are not a part of this acquisition.