Setting up FlashDevelop with Actionscript 3
Keith Peters has done up a tutorial on putting together an Actionscript 3 development environment using Flashdevelop, the Flex 2 SDK, and a variety of plugins/tools. It does take a bit of work to set up, but if you are looking for an alternative to using Flex Builder 2 or the command line for learning/working with as3, it’s a great alternative and definitely worth the effort.