Today I've activated my OpenID on Yahoo, So what is open ID? what problems does it solves?, rather than me copying and pasting in my blog entry , try to check this site
http://openid.net/
i was using something similar for Microsoft Sites called (Live ID) it is a single sign-on solution that save you the trouble from registering with several user names and passwords into different sites , so there will be one account for all sites (for technical people it is a unified authentication mechanism)
I was crying for something like this for ages, because i was sick of creating a new account for every web site I'm interested in
Till the next post, Leave you in peace
