Yup. Just Google her, and you'll come up with a lot of creepy stuff. Her religion, "theosophy," probably had a significant influence on Alistair Crowley (a notorious occultist popularly described as "the wickedest man alive"), who wrote an introduction to one of her books. Interestingly, his work fascinated Jimmy Page, who bought Crowley's mansion after he died. And from there the New Age movement exploded.
J.K. Rowling even references Blavatsky in one of her "Harry Potter" books. Harry refers to a book written by "Cassandra Vlabatsky."
Look at Xenu.com, old Crowley helped Parsons who helped L. Ron Hubbard.