Well, you might enjoy RobotLegs AS3: yet another lightweight micro-architecture for Rich Internet Applications.
It’s got the bits that I like about PureMVC (Mediators, Commands and Proxies) without any of the bits that I’m not so fond of (Service Locator, Singletons, casting casting casting!).
I’ve put the source up on GitHub, so feel free to Fork it and make it better:
Here’s a little demo:
(Please note: the API and usage has cleaned up a lot since this demo was built)
You can also view the demo here (with view source).
The demo app is perhaps not so great, but it demonstrates many of the framework’s features. AND, there isn’t a single cast in there! No actor casting, no payload casting, not any casting, not even for fun!
Update: RobotLegs Lives!