I wanted to create a quick list of Flex-specific plugins I find most helpful for my day-to-day Flex development. Mostly this serves as a reminder to me when I rebuild my IDE, but I thought others may find them useful too.

FlexFormatter - This is probably the plugin I use the most. In addition to highly configurable code formatting, FlexFormatter also has some excellent tools to assist in generating ASDoc comments. Installation is easy, just download and drop the jar files into your Eclipse plugins folder, then restart Eclipse.

FlexPMD - I recently discovered FlexPMD and wish I'd had this tool much sooner. The FlexPMD Eclipse plugin works with FlexPMD to help you spot and solve issues in your code. It comes with some prepackaged tests, but you can also create and customize your own. It encourages best practices code, and will help you improve your code before you push it to production. FlexPMD can be executed from ANT tasks, and there is plenty of documentation on how to integrate this into your Continuous Integration tooling.

ActionScript Framework Downloader - If you work with frameworks and other libs, this is a tool you cannot live without. It allows you to download common frameworks directly into your project with a couple of clicks. HUGE time saver! Read the installer instructions carefully, as it does require the SVN command line tools in addition to the plugin.

Flex Builder Localization Tool - Another tool I recently discovered, the Locatization Tool assists you in removing hard coded strings in your application and replacing them with calls to localization scripts.

Mylyn - Not Flex-specific, but Mylyn is a very popular plugin to assist with code versioning and issue tracking. I use it with JIRA/SVN and Trac/SVN. I won't go into it a lot here simply because so many resources already exist for Mylyn. But I do highly recommend adding it to your workflow!

If you know of any other "cannot live without" Flex plugins for Eclipse, I'd love to hear about them.