#DeleteFB

"Go here (working link above):
http://www.facebook.com/help/contact.php?show_form=delete_account

Click "Submit" and follow the instructions.

Your account will be deactivated for two weeks, and if you DO NOT USE FACEBOOK IN ANY WAY during that period, your account is permanently deleted.

I REPEAT: Your profile isn't deleted right away! You must NOT log in to, or interact in any other way with Facebook for at least two weeks, as it will cancel the deletion request. That includes NOT logging in to Facebook using any client (like the iPhone app or IM:s like Pidgin), NOT clicking embedded Like-buttons on other websites, NOT logging in to other services using Facebook Connect (like Digg) etc etc.

Hey, while your're at it, delete all your browsing/forms history and cookies as well, to minimize the risk of accidentally using your account!" (quoted from Facebook group that has since been set for archiving)

Candyman's additions: There are some things that I think are necessary as there is no gaurantee that Mr. Zuckerberg actually deletes anything, given the lucrative market he has stumbled into. Therefore here are a few of my own suggestions.

1) delete all photos.

2) Dont just REMOVE your personal info (ie. Name, birth date, location, etc.) but CHANGE THEM to something more fabricated. This way if the 'deleted' profile info is in fact archived it will be wrong, and if enough time passes, may not be able to be properly recovered.

3) delete EVERYTHING contained within the profile, exceptions of course include what I mentioned in step 2.

4) enjoy the freedom of not having your personal data at risk.

(more info coming later regarding their mobile app)