I just finished J.J. Luna's How To Be Invisible which is about keeping your personal information private. In particular, how to keep your name out of as many records as possible and how to keep your home address completely unassociated with your name.
Nothing in the book is anything I would ever do but I can see how if you have a stalker ex or worked in any kind of controversial or powerful job they are really good ideas with a lot of actionable detail. (The author himself spent some time as a spy in Franco's Spain.)
Certainly an interesting read in terms of how one normally thinks of interacting with the world. You may think of yourself as living a low-profile life, but it is an open book to anyone who cares to read it. Mustachians may avoid certain databases by not having a car or doing things like ordering pizza, but I didn't know about the controversy about a private company, Image Data, buying personal info from the DMV, funded by the Secret Service. Or there is a lot of information about scams or "pretexts" PIs can use to track people down. In general, it is a wake up call about how ridiculously difficult it is to maintain privacy.
Overall, maintaining your privacy is more expensive than not. (The author is NOT advising on ways to avoid income tax or hide funds.) I was often reminded of MMM's post, I don't remember the name exactly, but it might have been Get Rich With: Trust. Most of us are not going to spend extra money to needlessly stay under the radar our whole lives just in case we are ever thrust in the spotlight by being falsely accused of murder or something. The flip-side of MMM-optimism, however, might be that it's best to educate yourself so that you can competently respond to the situation if you ever do need to disappear. Then you don't need to feel threatened or afraid if you ever turn whistleblower or accidentally cut off a Hell's Angel.
The author does espouse mustachianism at one point! In order to avoid giving your social security number when renting an apartment, he says to pay 6 months in advance. In response to the question of what to do if you don't have that kind of money, he says "if you are that broke" then you need to stop all non-essential payments and expenditures on everything, including selling anything expendable on a payment plan like furniture or a luxury car, until you have $5000.
There was one area where privacy might save you money which is if you have particularly expensive cars, like, antiques, and you've bought it as an LLC (which he suggests for everything you buy), when it comes time to sell, you just transfer the LLC to the buyer. This means no transfer fees or sales taxes come into play because technically the ownership hasn't changed. I'm assuming that for most cars, the cost of maintaining an LLC would outweigh sales cost.
Another book I'm reading is To Save Everything Click Here: The Folly of Technological Solutionism. It's a very thoughtful book about how we talk about the role of technology and the underlying values beneath that discussion that most of us take for granted. I would recommend it.