  Motivated by ideas obtained from both ghost condensation and gravitational
Higgs mechanism, we attempt to find classical solutions in the unitary gauge in
general ghost condensation models. It is shown that depending on the form of
scalar fields in an action, there are three kinds of exact solutions, which are
(anti-) de Sitter space-time, polynomially expanding universes and flat
Minkowski space-time. We briefly comment on gravitational Higgs mechanism in
these models where we have massive gravitons of 5 degrees of freedom and 1
unitary scalar field (Nambu-Goldstone boson) after spontaneous symmetry
breakdown of general coordinate reparametrization invariance. The models at
hand are free from the problem associated with the non-unitary propagating
mode.
