Bebo
If you have not yet heard about or checked out www.bebo.com than I think that you are really missing out on something great!It's an address book that is done over the internet so that people on your contacts list can update their information whenever necessary and it automatically updates their info for everyone in their book.
So if I get rid of my e-mail address or run over my cell phone and have to switch numbers all I do is log in...Change the information...And all of my contacts have my most current contact info...It is a miracle! Plus they have photo sharing and journals and comments so you can post pictures....And comment on your friends' pics and leave little journaling messages detailing just how you managed to destroy yet another cell phone-complete with pictures of the deceased phone...And your friends can leave mocking comments....It really is a win-win situation. Check it out.
and they didn't even pay me to advertise. :P