Munich went open source / Linux a couple of years ago, ditching Microsoft. Using a big budget to convert everything and support employees etc. It was a huge act.

...Then they went back to Microsoft in yet another huge act, using a big budget. And then never revealed the budget for the last one. Which is really weird, considering its public money.

edit: just wanted to say that when idiots get power, there is always a way back. No matter how obviously stupid that would be