  With the advent of chiral fermion formulations, the simulation of light
valence quarks has finally become realistic for numerical simulations of
lattice QCD. The simulation of light dynamical quarks, however, remains one of
the major challenges and is still an obstacle to realistic simulations. We
attempt to meet this challenge using a hybrid combination of Asqtad sea quarks
and domain-wall valence quarks. Initial results for the proton form factor and
the nucleon axial coupling are presented.
