Today at an airport I sat down at a table which had a tablet facing me. I am not sure what it's supposed to do for people, but I realized that one thing it might be doing to me was watching me with a camera. It is full of nonfree software and there is no basis to suppose it isn't malicious.

So I put my coat down over it before sitting down.

Sure, there are other cameras in the airport, making recordings. We are under total surveillance by the state, there. But the tablet might be spying for various companies that have no access to the surveillance camera recordings. If there are two snoopers, and I can block one of them, that is an improvement.