Thanks,
Actually I'm pretty close to cracking this one.
Not sure what you mean about "not doing anything in PHP" tho. I've written the Rewrite rules in PHP and made it into a shell script which Apache will read when it does a RewriteRule in .htaccess
I think it's near to working, only think I can't quite figure is the correct syntax for the rewrite rule.
Currently I have
RewriteRule \.(wmv)$ $(nohotlink:$1)
where nohotlink is the name of my map.
I want to feed all files of type .wmv into my RewriteMap ( which is the PHP bit ). I'll go look at the tutorials now.
Thanks for the tip!