Keep modding parent up, please.
Everyone's opinion of L. Ron Hubbard today is strongly colored by the fact that he went insane at some point and took a joke way too far (by inventing Scientology as part of a casual bet with Heinlein over who could invent the best religion). I hate Scientology and all other religious cults (i.e. "religions") as much as the next rational person, but unfortunately it makes people forget the fact that LRH was actually a very good writer back in the day, including science fiction. He was contemporaries and friends with other sci-fi greats like Heinlein. People judge him now based on the craziness of the Xenu story, but I believe he specifically made the basis of Scientology as totally nonsensical as possible to demonstrate how easy it is to get people to believe in totally nonsensical made-up crap. He was making a point, originally, but then ran off the tracks with it because so many people fell for it that he convinced himself it was real (or at least worth taking advantage of to bring himself money and power).
All that aside, and this has been mentioned before a couple of times in other sci-fi discussions, the man was fully capable of writing excellent stories. I was fortunate to read _Battlefield Earth_ long before I had ever heard of Scientology, and even though I've devoured Heinlein, Asimov, Clarke, Herbert, Dick, Zelazny, and many other great collections of sci-fi before and since, to this day decades later _Battlefield Earth_ remains one of my favorite sci-fi novels. There's just something about it. It's incredibly well thought out logistically and filled with fascinating concepts that I've never quite seen replicated in any other sci-fi I've ever read or seen since then. There's a sort of plans-within-plans scheming aspect that strongly reminds me of _Dune_ at times. It's also very long, much longer than your typical sci-fi novel, so it's got the space to tell a very detailed and satisfying saga-type story with lots of different well-written characters. There are many concepts and scenes from the book that just pop back into my head now and then because they were just so unique and interesting. Oh, and it's just plain fun. It's a grand adventure. (One of my favorite parts was the little gray lawyer guy with the upset stomach at the end. Hilarious.)
The movie of course is a horrible joke. I was actually kind of surprised that someone with that much money to play with and who supposedly worships LRH as part of his religion would thoroughly massacre such a great book. The movie ended up containing about 1% of what made the book so good. So don't let that stop you from reading the book. If someone really did justice to a movie adaptation it could easily be one of the best blockbuster trilogies ever made.
So anyway, if you've got the balls go get yourself a copy of _Battlefield Earth_ and read it. Then when people ask why you're reading crap by "that Scientology guy" you can set them straight. My vote is definitely for L. Ron Hubbard being one of the most underappreciated sci-fi writers today.