Flex Studio

There has been a huge uptick in activity in the Flex Component space. It seems that many developers are making components and extending Flex in unique ways. Four projects to highlight are FlexLib, FlexBox, FlexComponents List, and Flex Exchange.
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Adobe APIs
corelib, mappr, flickr, youtube and more.
http://labs.adobe.com/wiki/index.php/ActionScript_3:resources:apis:libraries
APE (Actionscript Physics Engine)
http://www.cove.org/ape/
as3awss3lib
ActionScript 3...