ReactorGUI (Flash UI Framework)
ReactorGUI is a user-interface component library for building connected, collaborative applications with ActionScript 3.0.
Built on Adobe Flex and Reactor (Union's ActionScript client-communications library) ReactorGUI provides Union developers with high-level multiuser-application building blocks such as a user list, a room list, an avatar pane, a chat widget, a login window, position broadcasting utilities, and a debugging panel.
ReactorGUI is a free part of Reactor, and includes all source code so developers can study, modify, and extend ReactorGUI's component set without restriction.