Interestingly enough I've never really used WP for blogs and so never thought about the functionality of providing a method for users to sign up. I understand how to toggle the "anyone can register" function. How do I place a form field or whatever to allow someone to register? Also, I'm not interested in any plugins. Thanks.
The registration process for a WordPress installation exists by visiting.
http://example.com/wp-login.php?action=register
If you want to expand the registration page (and you change you mind about plugins) you could look at some of the following plugins.
http://wordpress.org/extend/plugins/search.php?q=register
I guess I want to create my own custom registration method. Maybe make a plugin. Thanks for the links.