Flash tweening animations can be done easier & with less coding using Movie Clip Tweening Prototypes.

Most features of Movie Clip Tweening Prototypes are from Fuse, which is a powerful Flash animation toolset.

There are also free .fla files of  very nice examples built with the prototype.

Note: This is an ActionScript 2 prototype.

Flash Tween Animation Prototype

A benchmark test of Movie Clip Tweening Prototypes & some other famous classes can be found here.

Flash Tween Animation