One of the cooler features of OpenID is delegation. This means, instead of having your OpenID identifier be
yourname.myopenid.com
it can be simply
yourdomain.com
Much easier to remember, right? And it's really easy to do, too! Here's how I did it.
First, sign up for an OpenID with the provider of your choice (note that Google, Yahoo, and AOL are all OpenID providers now, so you may already have one -- but beware that not all providers support delegation, either). I might be a little biased, but I prefer our very own provider at openid.stackexchange.com, so I recommend signing up with us at Stack Exchange.
openid.stackexchange.com
To enable your domain to act as a delegate to the OpenID provider, you'll need to figure out what your OpenID identifier is. This is always an URL. To determine your Stack Exchange identifier, visit your profile page on openid.stackexchange.com and look for the Use your own URL to log in link. Then click it!
This explains what you need to do. It's simple; just add two HTML header tags to your web page, like so:
<html>
<head>
<font color="red"><link rel="openid2.provider"
href="https://openid.stackexchange.com/openid/provider"></font>
<font color="red"><link rel="openid2.local_id"
href="https://openid.stackexchange.com/user/a0cd3405-f76e-429e-b935"></font>
</head>
…Once you've set this up, click my logins on your profile page, then click add new login… to add the new, delegated login to your account!