Once again, the folks over on DevShed are brining you a tutorial based around a "pat*" product - this time, it's using a patUser instance to authenticate your users.

In this new article, they show you how, using the patUser tool, to make a login for your users, and authenticate them from a local database. They give you the code, and the database structure to use, and even break down the user add/auth code in detail, showing you what each chunk does.

Some of the classes out there for authentication, like patUser are good to use, but I'd think mostly as a a learning tool. It's a good start, but once you really personalize your site, and want to set up things to happen after the user logs in, then you might want to consider moving above and beyond something like this.