Merge 78a77f60d4 into 3739f70db6

Update README.md

README.md

@@ -253,6 +253,7 @@ Google captchas use cookies to track users and rank their IPs.
 
 <img width="16" src="misc/check.png"> </img>  **Instead use**
 - [hCaptcha](https://www.hcaptcha.com/) - Privacy-first CAPTCHA for web, mobile, and more.
+- [mCaptcha](http://mcaptcha.org/) ([repo](https://github.com/mCaptcha/mCaptcha)) - An open-source CAPTCHA system with seamless UX.  mCaptcha uses SHA256 based proof-of-work (PoW) to rate limit users.
 - [OOPSpam](https://www.oopspam.com/) - No-captcha, privacy-friendly anti-spam, anti-bot API. Requires no personal data for detection. Supports popular platforms like WordPress. Privacy commitment in their mission statement.
 
 ## Commenting Engines
@@ -859,6 +860,10 @@ These tools are useful when sharing secrets, code snippets or any other kind of
 
 <img width="16" src="misc/check.png"> </img>  **Instead use**
 - [Monero](https://www.getmonero.org/) - Monero is cash for a connected world. It's fast, private, untraceable and secure.
+- [Conceal](https://conceal.network/) - Decentralized Finance, Private Transactions & Encrypted Messaging.
+- [Heaven](https://havenprotocol.org/) - Haven is an ecosystem of digital assets that enables users to convert 
+between volatile assets and stable currencies directly within their
+vault, in complete privacy.
 - Cash - Use person-to-person payments using physical notes and coins.
 
 **USE WITH CAUTION**