Then again, check the mobilecoin.com project. There is a whitepaper on the page, and there is a great wired (Just google wired mobilecoin.) article explaining technical details. If you know who is Moxie Marlinspike you will probably like this coin.
Mobile coin lacks some aspects of privacy, but it provides (It will provide, it still doesn't exist) enough privacy for 95% of people. People will be able to send money anonymously over encrypted chat clients like Signal and WhatsApp (These chat clients will be wallets at the same time.), so the focus is on normal average Joe's, comfort and security. It is quite nice, just open Signgal and send your friend money to help him or borow him, or pay someone without anyone knowing how much and what you have paid.

So, you see, we don't have enough privacy coins.