Coming from a world of Java, you may see a lot of shortcomings in the Flex world and wish you could have things like a logging tool (log4j), a lightweight IoC-container (guice) and a mocking framework (easy mock). All this is covered by FxPotpourri.
With FlexMT each flex program can be easily equipped with multi-touch operation. FlexMT supports symbolic and direct gestures like dragging, rotating or scaling and uses TUIO for touch detection. FlexMT is part of a Tabletop-Project at the FH-Trier.
Advanced Flash Preloader from http://preloaderz.com will provide well-dubegged, optimized, fast, easy and ready-to-use Flash/Flex/ActionScript solution. We will try to share good code for all preloading needs.
warpFX is a data abstraction library for Flex™ offering transparent data services between Flex™ and any AMF3 compatible server supporting some defined remote methods. warpFX ships with a server-side remote methods and AMF3 implementation for Helma.
The<spellcheck:*/> component provides spell checking capability for Adobe Flex 2.0 RichTextEditor and TextArea components. It's a simple replacement of the <mx:*/> RichTextEditor and TextArea components.
Interfuse is a workflow framework that joins ("fuses") the services, rules and objects of a traditional application with user-defined workflow. Interfuse is lightweight and designed to be embedded in existing Java-based applications.