Dynamic sub directory listing without redirect

Hi List, I am trying to allow dynamic URL's for my users to remember similiar to: www.mysite.com/joesoap So I want to use "joesoap" in a PHP script to pick up the user's details from a MySQL database. If the "joesoap" does not exist in the table I will handle that. So basically I have one file www.mysite.com/index.php which should do all the processing. I have tried with the apache .htaccess mod_rewrite, however when I echo $_SERVER['PHP_SELF'] I can't detect the "joesoap". It returns /index.php. Of course the easiest way is to do something like www.mysite.com/index.php?username=joesoap but that is too long and complicated for our users. As we have thousands of users, I don't want to create actual directories. Furthermore can this be done too (without a joesoap file): www.mysite.com/joesoap?show_extra_details=yes Any advice/links would be much appreciated. If I am barking up the wrong tree throw me a bone please. Thanks alot Terence