Interesting thing Thom brought up today. Two way communication from with the browser in flash - control flash from javascript.
This seemed to give the answers:
http://www.moock.org/webdesign/flash/fscommand/index.html
JavaScript can send commands to Flash by invoking built-in methods on embedded movie objects. Calling Flash methods works exactly like all calls to built-in methods on JavaScript objects (eg. document.write() or window.close()). From a developer point of view, this direction of communication is one sided–JavaScript methods control a Flash movie entirely in JavaScript, without requiring complementary code in the Flash movie.