Here's a neat idea. Wish I thought of it first.
ClaimID.com is a web site that allows you to assert your online identity. To say:
See My ClaimID for an example.
Now is this service necessary? Not really. I have a web site (you're reading it) and so I already have the ability to publish links to my other sites. And most people (normal people, like my sister or my nephew) don't have an online identity and have no need to create one.
But still, it's cool.
Disclaimer The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.