Interesting, sounds promising. The idea is good, but you must have objectives completed for the idea to be in full control.
For instance, the password for members can be easily cracked by many men and women in these forums and out. So, technically, there is no real way to 100% protect your members\' identities. What I do suggest, though, is a number of passwords. For instance: On the main BISM site there is a member page. It asks for the password. You are transfered to BISM page 2 (hosted on another site possibly, a free site like geocities though of course) where you must again write a password. You are transfered to a third site, with a final password, that transfers you to the final, and official, BISM web site.
Yes, this may sound rediculous, but there were several *other game* guilds that kept their members\' identities secret, but the passwords to the information were easily retrieved and usually were flooded on the boards inside posts. Occasionally there were money offers for the passwords.
Just understand that if you want to keep a secret, you must make sure it is kept that way.