  We consider a model of dynamical neutrino masses via the see-saw mechanism.
Nambu-Goldstone bosons (majorons) arise associated with the formation of the
heavy right-handed majorana masses. These bosons then acquire naturally soft
masses (become pNGB's) at loop level via the Higgs-Yukawa mass terms. These
models, like the original neutrino pNGB quintessence schemes of the 1980's that
proceed through the Dirac masses, are natural, have cosmological implications
through mass varying neutrinos, long range forces, and provide a soft potential
for dark energy. We further argue that these models can explain leptogenesis
naturally through the decays of the right-handed neutrinos.
