Kunekt

Kunekt‘s idea is to publish your contact information on your website (as a RSS-file), so that interested people can subscribe to it. This allows the subscribers to have the latest information. The information can subsequently be imported into your favourite address book.

This seems like a good idea. I remember other services that tried to create a central directory, which did not work. A distributed solution seems to be much better. It depends on whether the importing from RSS is a standard and the markup will become a standard. Kunekt allows you to create a RSS address card and they will host it. They also have import and export tools. I will add the file to my site.