A new backup software called Cucku has a weird backup solution which they call social backup. This so called "social backup" technique allows you to backup your data not only to your own PC but to your friend's PC as well, provided you have a friend who will allow you to do that.
To get started you download their free software and also arrange a friend who is kind enough to lend his hard disk space for your files. Now every time a file on your PC is changed, Cucku will make a local backup of the file and then automatically upload an encrypted copy of the backup to your friend's PC over the Skype network. Because the backup is encrypted your friend is unable to view the contents of the backup. Restoration of data works the same as with any other backup solution.
Cucku is designed to provide an easy solution for friends and family members to help each other with offsite backups. But it isn't limited to families and friends. Cucku can turn out to be very useful for small business owners for backing up a network of computers. Also laptop users can use Cucku to backup every files on their laptop to their home PC automatically.
Another useful feature of Cucku is that it keeps all versions of the files it has backed up. This means that you can restore a specific version of an individual file or all versions of files prior to a particular date and time. So if you accidentally change a file and then back it up, you can still recover the previous version from the back up. This also works with accidentally deleted files.
[via Tech Crunch}