Open-ID

To be fair, OpenID is a well-trodden path (unlike various other technologies that shall remain nameless), and there appear to be plenty of OpenID solutions, although many of them seem to rely on the same set of fundamental libraries, so that doesn't mean that the technology is necessarily well-understood even if the amount of common experience is considerable.

Sadly, like everything else, the original simple idea has raced away leaving a lot of people to abandon the idea of running their own provider, and it also doesn't help that people who supposedly accept OpenID sometimes reject identities from providers other than the big names because, paraphrasing one explanation I heard at one point, "you can't trust providers you've never heard of before". Obviously, OpenID is just about the identity and not whether that identity can be trusted with anything - something a Google-minted identity isn't going to help you decide anyway. And let us not consider the expanding interoperability matrix and all its accompanying problems.

I think we're going to see a lot more discussion around trust and decentralisation - for example, whether it is prudent to delegate any control over one's identity either by using a big-name service or by running one's own Internet-resident service on someone else's server - as people begin to question the centralised nature of their Internet interactions.