they are very scary....
I read a book, now almost impossible to get, called The Bare Faced Messiah
which was an unexpurgated bio of founder L Ron Hubbard. He was a penny-dreadful sci-fi writer in the 30's and 40's who realized he could make a fortune by starting a new religious movement - and did. There is actually a bona-fide quotation which has him saying something along the lines of 'I am going to start a new religion and make a million dollars'.
I won't go into all the details, or the ones that I can remember, but here are a few points.
They have a science-fiction version of 'eschatology' (a.k.a. the fate of souls) which is built around this (ridiculous fantasy) that the Earth used to be inhabited by an alien species who trapped the souls of millions in volcanoes, aeons ago. The whole race is now bearing the scars of this dreadful trauma, and only L Ron and his people know how to 'clear' you.
They sign you up for these extremeley pricey
sessions called 'auditing' and also insist you tithe a % of your income to them. Devotees have given accounts of spending literally hundreds of thousands of dollars on the teachings (which are sold, note, not given away).
If you question them or show signs of disloyalty you can be subjected to segregation, virtually jailed.
There is a lot of info out there, it ain't pretty. They sue anyone who tries to expose them. Time Mag ran a cover story on them called The Cult of Greed
in the early 90's, it was reputed to have cost Time Life almost half a billion dollars in legal fees in the 10 years following. Anyone who leaves the movement is classified as a hostile and harassed, followed and hounded.
An Australian senator read a big file on them under Parliamentary privilege earlier this year, detailing some very nasty cases of abuse, splitting of families and harrasment, but the Government was too busy fighting other fires to let an enquiry happen. It is a pity, they have tax-free status in Australia which is an outrage, considering they sell their material for thousands of dollars.
They have come very close to being banned outright in France and Germany.
My take: they're a vicious, evil, nasty, paranoid bunch of losers and parasites, who masquerade under Freedom of Religion laws, and I will never understand how people are stupid enough to let a huckster like Hubbard take them in.
Stay well clear
Postscript: let's see if the Scientology auditors pick this up. They will hassle the mods to delete it.