So far I have these 4:
Johannes Trithemius (1462 — 1516) Wrote extensively on the occult, but his books were encoded texts on cryptography and steganography, a practice he invented of concealing a message inside another message.
Aleister Crowley (1875 — 1947) Either a lifelong con-man, opportunist and traitor who campaigned against US involvement in WWI to Germany's benefit. Or he was a life-long agent of British intelligence, recruited while a student in Cambridge, whose most successful operation was to make German sympathizers in the US look ridiculous by declaring Ireland's independence while standing in front of the Statue of Liberty-
John Dee (1527 — 1608) Queen Elizabeth I's spymaster was also obsessed with angels. He spent most of the back half of his life attempting to commune with them to bring about a pre-apocalyptic unity of humanity.