What's the absolute minimum info one has to provide if one chooses to join FB?

[JEDIYoda]

A secret society that I belong to just moved their online forum to FB. I don't have an FB account. I don't really want an FB account but I know they'll be talking about me there if they see I haven't joined. So what personal info does FB demand in payment for their services?

go to the facebook page and find out...

Also not a very secret society if they use face book...