Bill Maher's Religulous was completely one-sided, presenting a totally biased and simplistic view of religion. I loved it!
It should be noted that, with a couple of exceptions, he doesn't exactly talk to the best and brightest religious personages. Nor does he give them time to make any good points; they're frequently interviewed long enough for him to make a joke at their expense, then he moves on to the next scene. He uses fundamentalism to paint with a broad brush all people of faith. Nor does he even consider any of the positive things that can come out of religion and faith.
However, the movie manages to succinctly make a number of good points here and there. One is to dispatch the notion that America was created as a "Christian nation". With some choice anti-religion quotes from Franklin, Adams and Jefferson he establishes that these guys were free-thinkers; to claim otherwise is revisionism. Second, in a nice little segment he backs his skepticism regarding the story of Jesus by alluding to commonalities between the Gospels and the myths made of many other historical figures of the Middle East. I.e. born of a virgin, born on the solstice, etc. One prior myth, that of Horus, is basically identical to that of Christ.
He spends most of the time on the big three monotheisms: Christianity, Judaism, and Islam. But there are a couple of diversions to look at Mormonism and Scientology (the funniest scene is where he preaches OT-III stuff like Xenu and Thetans to Speaker's Corner in Hyde Park, ranting like a lunatic).
I really like his monologue at the end, an extended diatribe against the damage that fundamentalists in power could do and a plea to recognize that doubt is good. I've transcribed it in the paragraph below.
The plain fact is, religion must die for mankind to live. The hour is getting very late, to be able to indulge in having key decisions made by religious people, by irrationalists. By those that would steer the ship of state not by a compass, but by the equivalent of reading the entrails of a chicken. George Bush prayed a lot about Iraq, but he didn't learn a lot about it. Faith means making a virtue out of not thinking; it's nothing to brag about.... Religion is dangerous because it allows human beings, who don't have all the answers, to think that they do. Most people would think it's wonderful when someone says "I'm willing Lord, I'll do whatever you want me to do." Except that since there are no gods actually talking to us, that void is filled in by people, with their own corruptions and limitations and agendas. And anyone who tells you they know, they just know what happens when you die, I promise you [they] don't. How can I be so sure? Because I don't know, and you don't possess mental powers that I do not. The only appropriate attitude for Man to have about the "big questions" is not the arrogant certitude that is the hallmark of religion, but doubt. Doubt is humble, and that's what Man needs to be, considering that human history is just a litany of getting shit dead wrong. (Bill Maher, Religulous 2007).