https://media.ccc.de/v/33c3-8034-build_your_own_nsa#video&t=2681 https://media.ccc.de/v/33c3-8034-build_your_own_nsa#video&t=... It is really easy to identify

https://media.ccc.de/v/33c3-8034-build_your_own_nsa#video&t=2681 https://media.ccc.de/v/33c3-8034-build_your_own_nsa#video&t=... It is really easy to identify a majority of users of such a dataset.