I like the idea of having a single ID for Internet. It reduces the burden of creating accounts everywhere. The ID could be used in any site that would like a non anonymous comment or activity. A request for ID info could pop-up for an accept button. There are solutions in the market, of course, but they have not yet got critical mass, I guess. The Id together with karma and voting would help a lot to select interesting comments.

A lot of our browsing activity is not anonymous anymore, I can see the ads are tracking me! So why not use this 'system' for something else?