Why does religion exist?

Arthur C Clarke once said "It may be that our role on this planet is not to worship God, but to create him." This quote seems to summarize the many aspects of religion in that all the aspects seem to point to one fact: Man created "God". Many of the considerations can be taken into account when attempting to define religion. Being that there are so many, including some that aren't very well understood, there …

…he (or she) has to interact with humans. I put more trust into a creator of the universe who sits back and occasionally looks in on our little planet. I just have a hard time putting my trust into a God who killed forty two boys for calling one of his followers bald. But what I think doesn't really matter. What matters is this: Religion is what you make of it. What do YOU think?