Flare is a collection of ActionScript 3 classes for building a wide variety of interactive visualizations. For example, flare can be used to build basic charts, complex animations, network diagrams, treemaps, and more. It is written in the ActionScript 3 programming language and can be used to build visualizations that run on the web in the Adobe Flash Player. Flare applications can be built using the free Adobe Flex SDK or Adobe's Flex Builder IDE. It is based on prefuse, a full-featured visualization toolkit written in Java. Flare is open source software licensed under the terms of the BSD license, and can be freely used for both commercial and non-commercial purposes.
It was developed by the Berkeley Institute of Design (BiD), a research group that fosters a interdisciplinary approach to design, spanning human-computer interaction, mechanical design, education, architecture and art practice.
Check their initial demo reel to see some of the visualizations that flare makes it easy to build. To get up and running with flare, take a look at the Flare Tutorial and the API documentation.