Have you seen the press about Pogoplug? Backup, streaming, sharing (photos, music, video, movies, documents, etc.), remote printing. Pogoplug is billed as your own personal cloud service.
Starting last month, they have a program that requires no hardware. It costs $29 for a lifetime subscription. You install it on all your computers and select the folders you want to stream, access, or share on the Internet. They offer free iPod and Android apps in the respective markets. There is a even a procedure to install on Ubuntu and share files to it.
I know a podcaster who uses it to co-locate backups with his buddy.
I think that this program will replace many of the cloud services that people are paying each month for. Flickr gone. Amazon Cloud Drive gone. Carbonite gone. Music streaming services gone.