Mollify - Web File Manager
Mollify is a web file manager for publishing and managing files hosted in a web server. Users can have access to different files and with different permissions. It has support to Search files, Extract zip archives, File uploading (large files are uploaded in small chunks), WebDAV support.
It has file preview support for file formats like flv, mp3, gif, png, jpg, pdf, doc, xls, html, xml, js, cs etc. User could do self registration and publish his documents. Each user and group could use different folders and it is fully configurable without revealing underlying file system.
Source code: http://code.google.com/p/mollify/