Ages ago in Dragon magazine there was an article that detailed a paladin of each alignment. There were two for true neutral that I think they were called Paramander and Paramandyr. One strove to maintain the balance of good v. evil while the other, in a more zealous role, attempted to enforce the balance by slaying those of extreme alignments.
I thought these were very cool and most, if not all - depending on the campaign, could be very workable. However, I have no recollection of their powers.
I think this link may be the article in question, but since it was so long ago that I read it I don't really recall.
http://members.tripod.com/Lord_Eadric/paladins/paladins.html
Check it out for yourself - I hope you find it helpful.
