At the urging of a certain judgment-casting developer friend, I've signed up for GitHub and created my first repository: skedaddle. Per the description, it's a very (and I mean very) bare bones MVC framework written in PHP.
The framework was originally written for my senior project at Drexel. My group looked at a couple different frameworks, such as CodeIgniter, but to save the time of learning a framework we'd never used before (and because it's supposed to be a learning experience) I set out to write my own. The project served as a testing ground for the framework, and every week I found a tweak or two that would make it just a little bit better.
A general rule of mine is, treat every project as if you were going to productize it. It forces you to keep your code clean and avoid hacks. Even though I had no plans to do anything with the framework beyond simply using it as the foundation for my senior project, it was written as if it were its own product, so it was fairly easy to extract for standalone use.
Right now, all the framework does is allow you to define routes (using regular expressions) that map to model, view and controller files. GET requests run the model and display the view, while POST requests run the model and controller. I'm trying to keep the base framework as minimal as possible, but there are a couple more features planned, such as making GET data available as an associative array, and the ability to include third-party modules.