http://archiv.tutorials.i2p/mirrors/nacl.i2p/links/index.html
XMPP Be sure to use OTR, no matter which provider you are using. Onion There are a lack of i2p xmpp servers, so I will post ones that offer a .onion.
All of these link to the clearnet.
Not all have been fully vetted by NaCl, do your best to see which are safe!