RewriteEngine On
RewriteCond %{HTTP_REFERER} ^http://hotlinker1.com/* [NC,OR]
RewriteCond %{HTTP_REFERER} ^http://hotlinker2.com/* [NC]
RewriteRule /* http://www.popuphell.com [R,L]
Something like that. You should not have an OR on the last RewriteCond, I've done that mistake couple of times
