Here are some Ning sites with PR again with all lists the PR is correct at the time of publishing
http://www.broadwayspace.com/main/authorization/signIn – PR6
http://lincolncenter.ning.com/main/authorization/signIn – PR6
http://www.diydrones.com/main/authorization/signIn – PR6
http://www.gnomedex.com/main/authorization/signIn – PR6
http://www.govloop.com/main/authorization/signIn – PR6
http://www.homebasedbusiness.com/main/authorization/signIn – PR6
http://www.informationzen.org/main/authorization/signIn – PR6
http://www.knaanmusic.com/main/authorization/signIn – PR6
http://www.landroof.nl/main/authorization/signIn – PR6
http://www.mugglespace.com/main/authorization/signIn – PR6
http://www.mybestbirth.com/main/authorization/signIn – PR6
http://www.copsonline.com/main/authorization/signIn – PR6
http://www.thetwilightsaga.com/main/authorization/signIn – PR6
http://www.greenpassport.us/main/authorization/signIn – PR6
http://library20.ning.com/main/authorization/signIn – PR6
http://www.myphdnetwork.org/main/authorization/signIn – PR6
http://www.navyformoms.com/main/authorization/signIn – PR6
http://www.teensforplanetearth.org/main/authorization/signIn – PR6
http://www.twittermoms.com/main/authorization/signIn – PR6
http://www.virtualworldsconnect.com/main/authorization/signIn – PR6
http://aspcacommunity.ning.com/main/authorization/signIn – PR6
http://atelier.rfi.fr/main/authorization/signIn – PR6
http://businessfightspoverty.ning.com/main/authorization/signIn – PR6
http://cherrytreerecords.com/main/authorization/signIn – PR6
http://come2play.com/main/authorization/signIn – PR6
http://epilepsyfoundation.ning.com/main/authorization/signIn – PR6
http://imsaturn.com/main/authorization/signIn – PR6
http://www.officialflo.com/main/authorization/signIn – PR6
http://community.essence.com/main/authorization/signIn – PR6
http://geeks.pirillo.com/main/authorization/signIn – PR6
http://knaanmusic.ning.com/main/authorization/signIn – PR6
http://friends.landmarktheatres.com/main/authorization/signIn – PR6
http://enriqueiglesias.com/main/authorization/signIn – PR6
http://education.ning.com/main/authorization/signIn – PR6
http://dukedigitalinitiative.duke.edu/main/authorization/signIn – PR6
http://conversation.wamu.org/main/authorization/signIn – PR6
http://community.sfsymphony.org/main/authorization/signIn – PR6
