Did You Use a Birth Plan?

I am wondering how many women used a birth plan, or at least prepared a birth plan, during their pregnancy?

Here is a good article about birth plans at the Mayo Clinic:
http://www.mayoclinic.com/health/birth-plan/MY00052/rss=5

I had a few ideas in my head about what I did/did not want to happen during my labor and delivery. I never wrote an actual "birth plan" out, as it was not encouraged to do so. I loved the doctors, nurses and educational classes I attended, which encouraged us to know what we want, what our options are, to be well-educated and be equal partners with our health care providers...but that writing a formal plan could be discouraging in the end, as women would then have their heart set on "The Plan", when the woman (and their partner) actually need to be more focused on being flexible than a written plan would allow.

What do you think? Did you use a birth plan? How did it go? How much of "The Plan" was actually followed through? Would you recommend a birth plan to others?