Dainty is a project mainly written in ActionScript, it's free.
A dainty little framework for dainty little projects
Dainty is a dainty little mvc framework for projects big enough that you want to seperate concerns but small enough not to need a real man's framework. It might also be useful in component development.
Dainty is pretty much an ActionScript 3 port of Colin Moock's Essential ActionScript 2 example.