You can use every running pool as an node.
addnode=del.poolerino.com
addnode=delete.okaypool.com
addnode=del.sumpool.com
The port you have to open in your FW is 45651, then others connect to you and vis versa.
I added those 3 peers to my config, 2 hours later I'm connected to those 3 peers, and only one additional peer...
37.187.134.204
98.126.98.139
98.126.190.28
193.242.149.63
Debug log shows it's attempting connections to a bunch of IPs, but they all time out. Ghosts of clients that have been closed?