Upload the index.php file to your site and remove or rename the index.html file (depending on your server setup; sometimes the html file will take priority over your php file). Then add your preferred URL using the query string:
http://example.com/?url=http://thefella.com
You can even leave off the protocol and http will be added in automagically:
http://example.com/?url=thefella.com
Forked from the original idea by Todd Motto