http://www.sephiroth.it/weblog/archives/2007/10/flex_frameworks.php

Luke Bayes and Ali Mills of PatternPark made a presentation for the Silicon Valley Flex Users Group (SilvaFUG) of 9 different frameworks and toolkits for creating Flex applications: Cairngorm, PureMVC, ARP, MVCS, Flest, Model-Glue: Flex, ServerBox Foundry, Guasax, and Slide.

Watch the presentation: http://adobechats.adobe.acrobat.com/p12266504/
See the slides: http://www.asserttrue.com/files/ApplicationFrameworks/index.html