Cucku is a new backup program come web service that attempts to take the best parts of each form of backup. First, Cucku lets you easily backup your important files and folders to your own hard drive and to portable drives you own. Then, in a unique twist on traditional online backup services, Cucku lets you store an encrypted copy of your files on your friends' and family member's computers through the internet using Skype.
This gives you the best of both worlds - the accessibility of a backup on a local drive with the additional security of a remote backup, all the while letting you keep your data on computers of people you trust instead of a datacenter.
From Cucku Blog