ElephantDrive

ElephantDrive is a complete cloud storage solution, offering secure cloud functionality tightly integrated with leading storage hardware solutions. ElephantDrive allows you to backup the data on your Synology NAS device to our secure cloud, enabling fast and affordable separate site protection for your most important files. The ElephantDrive runs natively on most leading NAS devices (NETGEAR, Drobo, QNAP, Western Digital, Thecus, Synology) and is optimized for the Synology DSM platform. In addition to cloud backup for NAS, the service offers built-in archiving, versioning, and file sharing.
Direct backup from NAS: ElephantDrive is natively integrated with leading NAS devices. No need for mapping the NAS to your computer!
Sync with Everywhere: The Everywhere folder automatically syncs across devices. Start working at the office desktop, pickup where you left off from your laptop at home.
Mobile Access: View, access, save and share your files from iPhone, iPad, or Android devices. And directly backup and upload files from your mobile devices!
Safe and Secure: ElephantDrive always encrypts data with AES 256-bit encryption before it even leaves your device! Transfer of the already encrypted data is also done using a 128-bit SSL secured channel.
Share a Folder: Share a folder with your colleagues - the changes that any of you make automatically sync to each others' devices. No more carrying around thumb drives or emailing files around!
Publish Links: Tired of emailing files or sharing them via thumb drives? Share files with your friends and colleagues with simple url links. You can even password protect the links!
Recover Deletions: Ever deleted a file by mistake or to save space, only to realize that you need it? Use Archive control to keep copies of deleted files and folders in your online hard drive.
Restore Old Versions: Wish you could go back in time and find an older version of a file? Now you can. All previous versions are easily identifiable with date and time.

The free version of ElephantDrive provides 2GB of account storage.