View the following.
https://about.usps.com/forms/ps1093.pdf
Follow the instructions to get a PO Box. To avoid mail containing harmful or annoying items, I recommend a small one.
Put the mailing address of your PO Box on your website, and tell people sending cash to it to address it to "YOURSITE," possibly appending "Donation Fund" if applicable.
Be careful to remind the reader that they need not put their real (or any) name on it, and that they can get stamps anonymously and location-randomized with ease if desired.
This also works amazingly if you want to charge for hardware or hosting, especially hardware or hosting that's privacy-focused.
Congratulations! Your readers/customers can send you money from almost anywhere without identifying themselves, and you can rest easy knowing that any dollars meant for you will reach you.