Perhaps the most high-profile authority to switch away from Microsoft is the German city of Munich.
The council that runs the Bavarian capital spent years migrating more than 15,000 staff to LiMux, a custom-version of Ubuntu, LibreOffice and other open-source software. Microsoft's attempts to persuade Germany's third-largest city from making the switch saw the then-CEO Steve Ballmer fly to Munich in 2003 for talks with the mayor.
The city said the shift had saved it more than €10m ($11m). More recently the authority has commissioned Accenture to undertake a review of the future of IT at the council, although, contrary to some reporting, no decision has been taken to move back to Windows.
Image: Björn Kindler