ActionScriptCheatSheet.com offers a number of ActionScript related cheat sheets, including one for both version 2.0 and version 3.0 of ActionScript. There are cheat sheets listing the available packages, details about specific packages, and overviews. A lot of the cheat sheets are PDFs that contain multiple pages worth of information and have a very easy to follow layout. Along with the ActionScript cheat sheets, the author has created cheat sheets for Adobe Air, Papervision 3D, and Apollo.

Besides all the great cheat sheets available, there are also a number of blog posts, book reviews, and articles about Adobe Flex, Adobe AIR, ActionScript 3.0, Papervision3D, Cairngorm, Thermo, and BlazeDS.

This site is definitely worth checking out. It has a lot of great information to help you get started, expand you current knowledge, and/or speed up your development time with any of these technologies.