dirsize  

dirsize is a command line based PHP utility. You need to have a local php interpreter (PHP binary; php-cli) in order to use it - it doesn't make sense to use it through a webserver! The sense of dirsize is to calculate the file size of any directory (and only directories) and their sub-directories. I made this one for my own usage as it really interested my how big this or that directory actually is.

Hosting Requirements: Linux, Cygwin
Price: Free

   FTP-Files-Navigator  

File navigator with icons linking to these files via ftp.

Hosting Requirements: PHP; FTP Daemon
Price: Free (GPL)

   net2ftp  

Features: Navigate the FTP server - Upload files - Download files - Upload-and-unzip - Zip-and-download - Copy, move and delete directories and files - Copy or move directories and files directly to a second FTP server - Rename and chmod directories and files - View code with syntax highlighting - Edit text right from your browser - Send files via email.

Hosting Requirements: *nix, Windows
Database: MySQL
Price: Free (GPL)

   PHPShare  

PHPShare is a simple PHP File sharing script. It allows you to run a simple FTP type program in your web browser! Its easy to setup and can run on most operating systems!

Hosting Requirements: Linux, Windows
Price: Free

   QuiXplorer  

QuiXplorer allows you to browse the files & directories on your webserver without using an external FTP-client. It currently supports the following functions: Browsing Directories, displaying Name, Size, Type, Date & Permissions - Viewing & Editing Files - Copying, Moving & Deleting Files & Directories - Downloading & Uploading Files - Creating (empty) Files & Directories - Searching for Files & Directories - Changing Permissions (UNIX style) for Files & Directories - User-authentication & management - Multiple languages (English, French, German, Dutch, Spanish, Russian)

Hosting Requirements: PHP 4
Price: Free

   OFM - Oveas File Manager  

OFM is one of the most feature rich and user friendly webbased file managers available on the net.

Hosting Requirements: PHP 4+; Perl 5+
Price: Free

   File Manager Plus  

File management system which enables the administrator to provide clients with their own folders on a server.

Hosting Requirements: Linux
Price: Free

   SmoothFileOperator  

Create an instant intranet for you and your team. Store your documents on your web server so you can access them wherever you have connection to the internet. With SmoothFileOperator it's easy to administrate your files online. Upload files, rename them, copy, move and delete them etc. SmoothFileOperator gives you explorer-like functionality - and more: Have a look at the upload log and you know what your colleagues have been working on. An especially interesting feature is that you can give descriptions to files and folders which are displayed right next to the directory entries.

Hosting Requirements: Unix, Windows
Price: Free (GPL)

   Wfolder  

WFolder is a set of scripts and pages that allow you to view, upload, create, edit, rename, and delete files in folder on your webserver using a browser. Uses a login to limit access. Quick and easy to setup.

Price: Free

   Replacer  

Have you ever run into a situation where you have thousands of HTML files which contain something (like an affiliate link code) that you want to update? If so, Replacer is the perfect utility for you. With Replacer, you're in control! You simply input the starting directory, the search term or phrase to look for, and the replacement text. You determine whether or not Replacer should act recursively (following directories within the starting directory) or limit itself only to the initial directory. You tell Replacer whether searches should be case sensitive or case insensitive. You even control how verbose Replacer is while it's working.

Hosting Requirements: *nix; PHP 4.2+
Price: $39.95