For more info about what Greensock can do, this great tutorial looks like the perfect thing to start with.
LazyFallback is an Adobe AIR application that converts banner ads from .swf to .jpg.
Flash is slowly being put down for the sole reason that it’s not supported by iOS devices, but Flash is still very useful for many tasks, including banner making.
LazyFallback converts swf files to JPGs (actually, a single JPG, but that’s still something), and allows you to do two things: set a delay before ‘screencapturing’ the swf, and set the quality of JPGs.
Flixel is an open-source flash game-making library written in ActionScript 3.
The library comes packed with tons of useful features: collision detection, object grouping, and an uber-optimized engine being the most useful, arguably.
Flixel is still being actively developed, and, so to say, although an omen of HTML5 game development is looming over the horizon, Flash developers are still busy making awesome games with this fine framework.