From the site:
SugarSync is instant and secure online file sync and backup for your PC, Mac or Mobile Device.
No need to email yourself important files or copy them to another computer using small thumb drives. With SugarSync you can automatically sync files and folders across multiple computers. Fire up your computer or notebook and your most recent files will be waiting for you.
SugarSync also has automatic, continuous, real-time backup for all of your files. Your latest files are accessible on our secure server from any computer or mobile device. SugarSync also stores the last five versions of your files for easy recovery.