Letting everyone know about the project I'm working on, which involves a comprehensive set of classes to aid in application development with Flash. Currently it's in AS2, but I will port it to AS3 when it becomes more or less stable and complete. Check out the project site for it. You can view the code right there or download it using an svn client. Also has a wiki and some api docs too.

Here's a repost of the news article just in case:

This is an open-source library of AS2 classes that aid in development of medium to large scale applications written in Flash. As we are all aware Flash has a lot of bugs and some things that are quite obvious to us or that work properly in other programming languages but are not well behaved at all in the Flash world. The aim of this project is to find fixes or workarounds for most of the bugs that don't place a lot of constrain on the programmer and provide an easy to use API. The project is yet to be completed for its first release, but I am making its progress publicly viewable to everyone.

Some features you'll find in it already:

* Unique id generation for all objects.
* Weak references
* Event handling/broadcasting
* Timers and repeating jobs.
* Logging mechanism with filtering features.
* Class name extraction from objects, method name extraction and other object utilities that help with typing.