Identity Management
Joel posts about identity management at flickr, and complains that you need to force your family and friends to 'sign up' before they can look at your pictures (or you must make your pictures public, which many users do not want to do).
When I ran into this while designing private areas for the ZIMoBLOG site, I went with a different scheme - you can simply require a password to view the site.
I think telling Grandma to come to http://stevex.zimoblog.com/ and type in a password at the bottom is much easier than telling Grandma to come to the site, sign up for an account, get a verification email, come back to the site and enter it and then go look at the pictures.