You can export sprite sheets from animations created in the Adobe Flash authoring tool. There are a number of free third party tools that enable this:

SWFSheet http://www.bit-101.com/blog/?p=2939

Zoe http://gskinner.com/blog/archives/2011/02/zoe-export-swf-ani...

This feature is also being built into the next version of Flash Professional (the authoring tool), with support for export to various JavaScript libraries (such as Easel.JS) for controlling the animation.