Among several AS 3.0/Flex experiments and projects, I must say that this is one of my favorites.

It is called Fisix Engine. There appears to be a few memory leaks in the fisix engine demo, however this appears to still be under development, I am certainly looking forward to seeing some more applications such as games, using this.

I have been trying for some time now to get my feet wet with Actionscript 3.0. It is an amazing language, but also a huge leap from AS 2.0.

Update: I just found this really cool ragdoll effect using the Fisix Engine, AWESOME!