Jungle Disk!

SpiderOak provides an easy, secure and consolidated online backup, storage, access, sharing & sync tool for Windows, Mac OS X, and Linux (Ubuntu, Debian & Fedora). SpiderOak offers a different approach to online backup, synchronization, and sharing. This difference is not just measured in our zero-knowledge privacy policy - the first one ever employed in this setting - but also in our flexible design in handling data from all platforms (Mac, Windows, Linux) and locations (external drives, network volumes, USB keys) in one centralized account. »

SugarSync lets you synchronize, backup and remotely access files and folders across your PC or Mac. You can also remotely view files from Windows Mobile, Blackberry, iPhone, Symbian and Android.

SparkleShare is a Free Open Source syncing tool. Its light, secure and easy to use. SparkleShare allows you to setup your own servers so you always keep control on your data.

Syncany is an open-source cloud storage and filesharing application. It allows users to backup and share certain folders of their workstations using any kind of storage, e.g. FTP, Amazon S3 or Google Storage.

Minimalist Drag & drop file sharing JS applicationDrag, drop and share

The only automated sync, back-up, collaboration and file management service powerful enough for a business user and easy enough for a novice. Secure, anywhere access to your files.

Get 5 GB of full featured Online Backup for free. Features include Automatic Backup, True Archiving, Versioning, Continuous Backup, Mapped Drive Backup and Web-based Backup Management.IDriveSync syncs files online across multiple PCs and Macs. On installing and logging into the application, it opens up a 'Sync' area where you can add the files you wish to sync.With iDrive Sync you can Sync up to 5 computers: Once you have new data into your Sync area, your Sync data starts getting transferred online, or 'Syncs-Up'. This essentially serves as an online backup of your data. Now, if you simply install and login on multiple PCs / Macs using same authentication, the synced data is 'Synced-Down' onto those multiple computers.Anytime you make a change to synced data anywhere on those multiple computers, all the computers will shortly reflect the modified data. »

Freehold - An open, secure, and lightweight platform for your files and data.

CmisSync synchronizes files to/from any enterprise file server.It looks very much like Dropbox, but synchronizes with an existing file server instead of synchronizing with Dropbox's server.Can synchronize with Alfresco, Documentum, FileNet, SharePoint, Nuxeo, NemakiWare, eXo Platform, and any other CMIS-compliant server. Not cloud-based: CmisSync can work on local networks without Internet.

Mozy is an online backup service that offers a set-it-and-forget-it solution for backing up all of the important files on your computer. With MozyPro, there is no extra hardware to buy, no setup fees, and with our automatic backups, no additional management required to oversee it all.

ASUS WebStorage offers online storage with auto data backup for nearly 3 computers, auto data synchronization, and data sharing amongst others.

OpenDrive is a remote drive for your computer, that allows you to store, sync, share, link, sell, advertise or back up files from your computer on the Internet with free 5GB.