what i do is go one step further and instead of using the flv url in the embed code you just use a simple dynamic swf url
so instead of adding all your params to the swf flv player in the embed code like logo=&link=&file=
you just use <embed src=http://mysite.com/swf/1789234.swf>
the swf folder uses htacces to run thru a php script the php script checks referrer and only makes the asx file if the swf is hotlinked ( so you can display different/more/less ads when they are on your site compared to when someone hotlinks or uses the embed code ) , plus you can have super short embed codes instead of long ones
