I'm an action fanatic.
Atheism is a religion itself complete with fanatics and bigots.
I'm a Star Wars fanatic.
I'm not a truthiness fanatic, I'm truthiness's father.
I found draft resistors very conscientious, reasonable, and not fanatics.
The only ones who make things change are fanatics. If you're not a fanatic around here, you can't cut it.
Nothing ever gets done unless it's done by a fanatic.
I would do fragrance. I'm a fragrance fanatic.
I love research. I'd go so far as to say I'm a research fanatic.
Ive always been a health fanatic.