gcrider, the current consensus in the scientific community on the subject is that, in the case of buttered toast, the operating principle is the presence of butter determining the orientation of the object during the fall, with the toast being merely a repository for the butter.
Therefore, one could theoretically achieve perpetual motion simply by buttering the back of the cat and dropping the feline.
P.S. Scientific American once had an article on the subject. The author speculated that for buttered toast, a piece of toast is just the right shape/size for turning over once when dropped from table height, which would explain the fact that it most often lands butter-side down.