This is the Wikipedia entry on Reformed Epistemology and the Great Pumpkin objection, which I alluded to earlier.
It is tempting to raise the following sort of question. If belief in God can be properly basic, why cannot just any belief be properly basic? Could we not say the same for any bizarre aberration we can think of? What about voodoo or astrology? What about the belief that the Great Pumpkin returns every Halloween? Could I properly take that as basic? Suppose I believe that if I flap my arms with sufficient vigor, I can take off and fly about the room; could I defend myself against the charge of irrationality by claiming this belief is basic? If we say that belief in God is properly basic, will we not be committed to holding that just anything, or nearly anything, can properly be taken as basic, thus throwing wide the gates to irrationalism and superstition? (p. 74)