Read 36 of these and consider almost all of them mainstream.

Cult would be Arthur Bremer's Diaries, the Letters of Emily Dickinson (or D. H. Lawrence), Whitehead's Process and Reality, T. Lobsang Rampa's The Third Eye, Ouspensky's Meetings with Remarkable Men, Grave's Greek Myths, Keuls' Reign of the Phallus, N. O. Brown's Life Against Death and Love's Body, G. Spencer Brown's Laws of Form, Fuller's Synergetics, A Pattern Language, Saberhagen's Berserker books, A. O. Lovejoy's Great Chain of Being, anything by Gertrude Stein or Laura Hobson Riding, Burgess' Clockwork Orange, Levi-Strauss' Triste Tropiques, Braudel's Civilization and Capitalism, Grunbaum and Shepherd's Tilings and Patterns, Flannery O'Connors letters, Key's Subliminal Seduction, Penrose's The Emperor's New Mind-- and so endlessly on.
posted by jamjam on metafilter, about the torygraph list below