At IndustryNext, we are in the interesting position of building cutting-edge projects, with cutting-edge tech for somewhat more established companies than your typical web 2.0 startup.
Part of keeping the speed and quality high is leveraging tools for code analysis and code generation to help keep a handle on dynamic language development. (E.g. I wouldn't ban the use of eval in Ruby, but I'd sure as heck want a tool that can tell me where in the codebase it's being used, and why.) In some cases, we're pioneering these methods.
Generating consistent code from models is a step in this direction. (In JavaScript, just guaranteeing consistent variable names can save no small amount of debugging.)
In order to make it easier to play with object models in ActionScript 3, I spent a little time integrating Cay Horstmann's lightweight Violet UML modeling tool with David Holroyd's metaas library for manipulating ActionScript.
The result is VASGen (Violet UML ActionScript 3 Generator) 0.1, an initial release of a free code generation tool that supports generating classes, interfaces, field, properties, methods, and various types of relationships from Violet's Class Diagram editor.
The project page includes details on what works and what doesn't in this release. If you build applications in AS3 and you like UML models, please give it a try and let me know what you think.