It's been quite a while since I've programmed in AS3, but something I found quite useful for communication between SWFs was the LocalConnection class. The SWFs don't need to be on the same page, or even the same browser. I suspect that the BBC iPlayer desktop application (built with AIR) uses this under the hood to trigger a download to start when you click the download button on the iPlayer website.
LocalConnection itself is fairly crude, it can listen for data coming from any other LocalConnection which knows its connection name, and it can send data to any other LocalConnection by name. There's no mechanism built in for knowing where received data had come from, that has to be implemented yourself. A quick code example:Read More