No encyclopedia of loons, cranks, crackpots and morons will be complete without including the legendary Sylvia Browne. Browne is a psychic and leads the Society of Novus Spiritus, based around the teachings of her channeled "spiritual guide" Francine. She’s also a devout Christian, and advocates both reincarnation and the afterlife (and, obviously, the possibility of talking to the dead).
Brought to fame through multiple television appearances - notably including regular appearances on the Montel Williams Show, where she notoriously failed to pass even a single half-serious test of her abilities (in other words, she employs the old conjuring trick of cold reading). A video of one of her blunders on Montel's show can be seen here. She has managed to build a decent following and pretty widespread fame. She has also attempted to claim James Randi’s million-dollar challenge, but after having made the initial testing arrangements nothing came of the attempt.
A brief biography can be found here.
A much more thorough exposé here (in particular here).
Browne doesn’t like these sites.
Claims, among other things, to have had a chat with the late Michael Jackson, but her specialty seems to be telling suffering parents where their lost children are, usually being dead wrong (several bad scandals here).
Diagnosis: Endlessly moronic kook; fraudster, but presumably unaware of it. Has a large group of followers.
This entry also indicts her son, Christopher Dufresne, who is a psychic "of powers equal to his mom's" (a claim which is surely correct).