We talk about software a lot here, but I was curious what other physical steps people take to protect their privacy. I’ve gotten in the habit of putting tape on any laptop I use that is running Windows (unless it has a built in cover like a Framework or ThinkPad), but I am guessing there are other techniques that are helpful to support privacy while using devices.
Certainly, you can take a look at what NovaCustom offers for their laptops:
Here are three value-added examples:
| Privacy and Security Options | Tooltip | Price |
|---|---|---|
| Camera and microphone module permanently removed | We offer an option to permanently remove the webcam and microphone module for those who are concerned about their privacy and don’t need an internal webcam and microphone. If you select this option, the camera and microphone module will be removed from the chassis. There is no option to undo this. | 39 EUR |
| Privacy screen (pre-installed) | If you select this option, we will apply a privacy screen on top of the laptop. The privacy screen is designed to restrict the viewing angle of your display, making it visible only to you when you’re directly in front of it. This prevents curious onlookers from seeing your sensitive information, providing you with peace of mind in any public setting. | 79 EUR |
| Tamper-evident screws and packaging | The laptop is packed with multiple boxes. By default, we use NovaCustom tape. But if this option is selected, all boxes are provided with tamper-evident tape that leaves an OPENED print when opened. The tape cannot be reapplied, making it immediately obvious that the package has been opened. Furthermore, all laptop screws are covered with a glitter substance. Should the laptop have been opened, you will notice that the laptop screws either aren’t covered with the glitter substance, or the 3D patterns of the screws have been changed. | 75 EUR |
If you want more examples, I can enumerate them.
I use Datablock cables for pretty much everything, that just needs charging. While I do like them, but to be honest, I don’t think I have gotten any real privacy or security benefit out of them. The best use case I have found is with cars with CarPlay and Android Auto. I don’t get annoying pop-ups every time someone plugs their phone into my car.
Port Blocker/Locks: I don’t have any, but there are a few niche use cases for them, mainly for shitty public PCs and servers with many unused ports, but I don’t think there’s a real benefit for personal PCs when you can disable unused ports in the BOIS for most PCs and can use USBGuard.
Mic-lock: I would say borderline useless because it’s very easy just to change the source of audio, but there may be niche use cases for cars and smart devices like TVs idk. I did buy a few for testing because I wanted to see if they worked in cars, but my car only have USB-A and don’t have AUX.
I could try in different work cars, but I’m lazy, and never got around to it.
Faraday bags/cages: There may be use cases, but I never really found a personal use for them, while I do own a few, but I only bought them because I needed travel bags for a few devices, and I thought it was funny with faraday bags.
Privacy screen: 
There are also modding, like removing the webcam, microphone, and Wi-Fi card etc.
TLDR: I wouldn’t recommend any of them besides privacy screens and FIDO2 Keys unless you have a niche use case for them, and even then I think there are better things to use money on if you want to improve privacy or security.
Possibly unrelated, but I have a personal rule of thumb for preferencing wired peripherals over wireless unless I have some specific reason not to.
I haven’t needed a laptop in a while. Since I currently have desktops, I don’t have a mic or camera at this point unless I actively plug one in.
Physically disabling a laptop mic probably isn’t doable for most people.
I am curious what would happen if I stuffed wax into the holes. But I suspect it would essentially muffle voices and possibly make keylogging with the mic easier - since the internal vibration might be more prominent.
I do use exclusively wired headphones in public and have for years. Bluetooth is convenient in the office or at home where I probably have far bigger concerns by the time someone is close enough to monitor it. But I don’t really trust its security in public.
After whisperpair flagged headphones that I owned until recently I also don’t think I will anytime soon.
The thing is, you don’t really need physical security if you control the software. The reason you need to physically unplug cellular models, microphones, and cameras in cars is because you can’t trust software switches, if they are available at all.
some laptops have a webcam privacy shutter, most thinkpads have this AFAIK.
I have transitioned to “hat guy” and I’m not even balding. I just wear a hat around surveillance camera areas and sometimes sunglasses even when getting groceries as POS systems have cameras in your face.
I don’t know if it actually achieves much, but it’s an easy way to even slightly obscure my identity without affecting my daily life.
Also, it may not be relevant as a “physical” privacy step, but using a fake name(s) for nonessential services when it is required (e.g., loyalty card pseudonym). Also, just not using apps for loyalty perks and only using physical cards.
I don’t really worry about privacy outside of Internet-connected devices. Beyond running free software where you can (PC, laptop, phone, networking appliances…), you want to make sure other devices that have no good reason to be talking to the Internet don’t. That includes TVs, home appliances, cars, and possibly other things.
Like others here however, I don’t share phone numbers with companies, provide a unique email (yourcompany@mydomain.com), and use fake names. I also pay cash when it’s practical to do so.
It’s not quite physical, but you can disable cameras and microphones at the BIOS/UEFI level which should in theory make it inaccessible to the OS.
Buy a shredder and shred any sensitive or personal documents rather than simply putting them in the recycling bin.
The (non-coated) shredded paper bits can even be composted if that’s something you have access to.
Lots of great advice in this thread! I’ll add that you can manually tamper protect your laptop: How to tamper protect a laptop
Another form of tamper evidence is using a private security system to monitor your devices while you’re not watching them yourself.
This is good advice. Fortunately I get very little snail mail nowadays.