really very small file manager

This is a very small file manager written in PHP4. The author notes "I made it because there was not really small (one file) solution for this, written in PHP. The real idea for usage is to build extensible pseudo hosting solutions running on one and same user_id. The script is usable for putting in password protected folder in order to edit your own website, without FTP access (is really cool) The design is simple because I expect those file to be included in a template. The includer must provide the authentication (and to set working directory and URL). The script works with PHP4/Linux and uses cookies and javascript on the client side. I also expect some problems with Netscape Navigator, but nothing found yet"