OpenJabNab

OpenJabNab is a software server that you can install yourself.
Open servers :

Nabisdead

Nabisdead is an open server.
http://www.nabizdead.net/ More information : http://nabaztag.forumactif.fr/t13218-serveur-experimental-nabizdeadnet

OpenNag:

OpenNag is an open server. http://www.opennag.byethost5.com/
More information : http://nabaztag.forumactif.fr/t13262-opennag

MybaztagServices.

http://mybaztagservices.appspot.com/
More information : http://mybaztagservices.appspot.com/about

Ptilu

Server is waiting for software. http://nabaztag.ptitlu.org/
For more information, please contact @PtitLu