The IBM developerWorks site brings the community another great tutorial today, this time looking at the CakePHP framework and the creation of a simple application with it.
In "Cook up Web sites fast with CakePHP, Part 1: Adding related information and services", they build a sample application (Tor) from the ground up (installation guide and all) that will take in a username and password on a login page. Their goal is to show you how much time you could safe by using the framework over just the usual library-based (or procedural) programming methods.
You will need to be a bit familiar with PHP and the Model/View/Controller design pattern before you get started here, but if you have that down, you can just jump right in. You'll also either need to register with the site or log in with your account information to get to the good stuff.