Bonkey is a simple to use backup system. It can backup to most storage devices, but it is specifically designed to be used with Amazon S3, which provides cheap online storage. You choose which files need to be backed up, select how often, set the destination and voila! your files are backed up. It runs on Windows and Mac OSX. It's open source, so you can download the code and tinker if you so desire.
backup to multiple locations, including Amazon S3, SFTP, FTP, Windows shares, and local disks;
backup Microsoft SQL Server databases;
backup automatically at a set interval and at a set time if desired;
backup only modified files, or a snapshot of the files you select;
compress and encrypt files during backup;
be configured to email any errors during backup to you;
allow drag and drop transfers between different locations; and
show built-in help.
runs as a Windows service: no need to login for it to start; uses less memory; and is invisible;
summary screen shows you all you need to know and makes managing your backup groups easier;
file transfer mode for easier drag and drop transfers;
synchronisation to remove out of date files from backup targets;
built-in restore wizard to restore to a folder or original locations.
Other things worth mentioning:
no spyware, adware, ads, viruses, spam, trojans or STDs. Just the backup software;