You might be aware of the Adobe Flex, which is used for the development and deployment of cross platform Adobe Flash based rich Internet applications. Adobe Flex is behind most of the well interactive rich internet applications you come across now a days. Adobe is also providing very good software kit for Flex development called Adobe Flex builder which is available for both Windows and Linux platforms.
If you are still new to Adobe Flex, then here is a nice resource center which can tell you about the basics of Adobe Flex and tutorials to get to much closer to Adobe Flex based application designs. Also you can find the free components and themes required for your rich internet application.
If you want to have a practical exposure, you can download the trial version of Adobe Flex.
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