[acebarry]

A similar project is I2PBote[1]. It uses a similar DHT method for mail, but over I2P[2]. As with Freemail, this is inside of the Bote network only.

If the DHT doesn't suit you, I2P also runs a mail server in their network that can relay out to normal email. Ships with I2P by default.

[1]: http://i2pbote.i2p.us/

[2]: https://geti2p.net/