PHP has been my favorite programming language (or scripting langauge, if you choose to be like that) since I started working with it a few years ago. While I was teaching myself the language, I developed a few little programs that I am very proud of. Hopefully one of them will work for you the way they have worked for me!
I developed ProPHP as an ad swap network I wanted to create. When I was "finished," I decided to release it as an installable package. Please note that I haven't put any work into this project since 2006 - 2007-ish - and there is a security risk with it. It's easy to fix, but I haven't done so yet.
This project was one for the ages! This project tought me a lot more about file management, databasing, encryption, php's readfile() function, and a whole lot more.
This project is essentially an online flash drive - the user logs in, and uploads their files (the administrator(s) decide what kinds of files, their sizes, the max number,
etc of files that can be uploaded). The user then has the option of downloading their files individually.
Look at the project page for more specific information as to how the program works.