This may sound silly but does anyone use an online address book that you can share with other people ? Yeah I could just use my gmail address book but then if my wife or someone else wants an address they would have to log into my account.

Something where other people could add and edit addresses would be nice.

Not silly, maybe lazy.

I was going to suggest an online LDAP server, but it appears that no mail clients have the ability to add or edit contacts on an LDAP server. Which sucks.

I was thinking something like a wiki maybe but I would want it to be private.

I found a couple online address books but none that you could share.

I suppose that some people use social networks for this purpose. I think LinkedIn has vCard export support. That means you could ostensibly scrape your buddies' vCards and use that to build/rebuild your contacts. Hardly ideal for a variety of reasons, but there you go.

The problem is you want something online that anyone can access but then want it private.

So you need some kind of username/password security. You can't have it both ways really.

Or would you like to say share contacts between GMail accounts?

Exchange Server can do that with shared contacts...

Yeah, it does. I looked into this when I was getting the wife started on Thunderbird.

I've not tried it in anger, but I suspect that (if you're using Thunderbird), a combination of SyncKolab and shared IMAP folders would do the trick nicely. If your mail client allows you to store contacts in IMAP, that'd be even better.

I do this, in a much less technical way: I was allowed 4 email addresses when I signed up for my internet service, needing only 3 for the family, I set the 4th one up as a dummy, with the family address book: Each of us only has to set up "remember this password", and we've got instant access to the address book.

eGroupware may be the answer...
http://www.egroupware.org/

You can host your own server or pay them to host one for you.
http://www.stylite.de/EGroupWareHosting

Full LDAP access, shared addressbooks, private addressbooks, lists, decent web interface. vcard, and DAV access.

Also does calendaring...

I set it up at home on a virtual machine and sync all our various linux boxen to it to various degrees.

Thunderbird/Lightning link to the calendar via CalDAV
Thunderbird uses LDAP for the addressbook.
When TB can edit LDAP then it'll be cool.

There is also the http://www.plaxo.com/ approach where you invite other people to update their own contact information. However some caution is probably in order, as:

- they are now owned by Comcast
- they have been flamed in the past for spamming your friends
- they haven't been playing nicely recently with people using their API to sync to the iPhone

I should say that I haven't actually used them myself, I was considering using them and http://www.nuevasync.com/ to sync contacts and calendar data to my iPhone, but got scared off when Plaxo blocked access to their API from nuevasync's servers.

Google docs and a shared spreadsheet file?
But I am still waking up...