1948 Cadillac - Cadzilla - Billy Gibson - Boyd Coddington

Celebrity Owner: Billy Gibbons

The Cadzilla may not be a bona fide supercar but we just don't care. This thing is too damn sexy for us not to include in this list. Created by late hot rod designer extraordinaire, Boyd Coddington, the Cadzilla is one of the most coveted one-off custom cars of all time. Want it? You'll have to wait until ZZ Top front man Billy Gibbons kicks the bucket.