Just knew that Google Profile gives us better URIs [via TechCrunch]. The old (but still work) URI is http://www.google.com/profiles/115422682039760465813, which is awfully long and you cant guess whos that by seeing the URI. The new one is like http://www.google.com/profiles/livibetter which is the same username of Gmail box. So, you probably want to put a dot in if you use your real name, for example, you can have http://www.google.com/profiles/livi.better as if you can do for your Gmail: livi.better[gmail]. That also works.

Go to edit profile1, scroll down to bottom, you will see the option to have new style of URI. If you click on see more options, you will also have an option like http://www.google.com/profiles/115422682039760465813, but I doubt that anyone would use that.

[1]http://www.google.com/profiles/me/editprofile?edit=t#about is gone.