FlashDevelop is a free and open source code editor for ActionScript 2, ActionScript 3 & MXML and HaXe. 
OpenLaszlo is an open source platform for the development and delivery of rich Internet applications. 
Salasaga is a free, easy to use GUI authoring environment that helps you create visually impressive and actually useful learning material.
Initially similar to Adobe Captivate, but will eventually incorporate an AJAX (browser based) playback capability for advanced content. Flash has at least one serious design limitation (from my POV) making it nearly useless for comprehensive eLearning, and this appears to be addressed by the existing capabilities of AJAX in browsers these days.