Research Statements--How do you write one?

Greetings all

So, as miraculous as it now seems, I will soon be looking for a faculty position. My CV is in order and now I am trying to draft a research statement. I wonder if anyone has any comments or thoughts about content, formatting, length etc. Also, if you have any advice—things to do or not to do that would be really useful. I wonder too, whom should I show my research statement to when I think I have a reasonable draft?

Thanks for your thoughts!