Dropbox - Online Sync and File Sharing
CKFinder - CKFinder is a powerful and easy to use Ajax file manager for web browsers.
ownCloud - ownCloud is an open source project enabling businesses to host their own cloud storage while maintaining regulatory and compliance needs.
Flmngr - Free PHP File Manager
Google Drive - Access and sync your files anywhere
Tiny File Manager - Web based File Manager in PHP, Manage your files efficiently and easily with Tiny File Manager