Sharing your source code is easy in Adobe Flex 2. After a quick glance at the Application class in the Flex API, you”ll find that the viewSourceURL property will allow you to open a new browser window at which your source would be stored. You could point it to a specific file or zip as well as a directory. Either way, you are able to share your code with very little effort.
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" viewSourceURL="http://www.robrusher.com"> ... </mx:Application>
UPDATE: For Flex Builder 3 they added a simple selection option that will include the source for you. Select from the menu bar Project > Export Release Build… And then in the dialog, check the box for including source and select the objects you’d like to include.
Thanks Jason for reminding me to update this post.