The Electronic Frontier Foundation develops several PETs. The source code of these projects can be found in the EFF Github repo.
The following of particular interest, but you may want to explore the whole repo.
- Panopticlick is a website will analyze how well your browser and add-ons protect you against online tracking techniques.
- PrivacyBadger is a browser add-on that stops advertisers and other third-party trackers from secretly tracking where you go and what pages you look at on the web.
- STARTTLS Everywhere implements encryption of SMTP traffic using the STARTTLS mechanism, in a more secure fashion than the reference implementation.
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