|The page you are viewing is simply for OpenID Identification.
Currently it delegates the actual authentication to a dedicated OpenID provider.
If you wish to do the same for yourself, it's ridiculously easy. For the simplest case, like this page, there is no programming!
First, register for an OpenID account at any provider you wish. Then, simply add some HTML to a page on a site you control and that URL will become your new OpenID Identity!
Here are some how-to links for more info: