Features (straight from the horses mouth)

• Browse through Files and Folders on your Server
• Rename, Delete, Move (Drag&Drop), Copy (Drag + hold CTRL) and Download Files
• View detailed Previews of Images, Text-Files, Compressed-Files or Audio Content
• Nice User Interface
• Upload Files via FancyUpload (integrated Feature)
• Option to automatically resize big Images when uploading
• Use it to select a File anywhere you need to specify one inside your Application’s Backend
• Use as a FileManager in TinyMCE
• Provides your Client with the most possible convenience ( ;D )

The back-end is in PHP but you can port it to whatever language you’re working with. The file manager is also released under the MIT-License. This is currently his RC1 (1st release candidate, for those not in the know). Head over to check out his demos!

Great job, Christoph!