I've been meaning to experiment with this for some time and was reminded of it with the recent release of FlashInterface. Currently there's no Flex 2 component for Yahoo Maps and since Flash 9 content can't talk directly to Flash 8 content I wondered how one might use the Yahoo Maps Flash component in a Flex 2 application I always knew LocalConnection was a possibility but hadn't thought about using ExternalInterface until I came across the solution I mentioned above. I figured this would be a great chance to try out FlashInterface and complete my proof of concept all in one shot.
I'll post the source code soon as I plan on making more updates to this. I might also use it as a chance to play with UrlKit some more and knock out another task I've been meaning to get done. There might be a few issues with this example right now, I've noticed that the mouse handling seems to be a bit funky when one tries to click on the map marker. I think the Flex application is intercepting the click before the Flash component is so I'll have to fix that.