Depende da quantidade de dados, música e vídeo que ocupam muito espaço. Para aqueles, sugiro que você configure (ou alugue) um servidor de armazenamento e use rsync .
Para os seus documentos, sugiro Dropbox
O Dropbox permite que você sincronize seus arquivos on-line e em seus computadores automaticamente.
* 2GB of online storage for free, with up to 100GB available to paying customers.
* Sync files of any size or type.
* Sync Windows, Mac and Linux computers.
* Automatically syncs when new files or changes are detected.
* Work on files in your Dropbox even if you're offline. Your changes sync once your computer has an Internet connection again.
* Dropbox transfers will correctly resume where they left off if the connection drops.
* Efficient sync - only the pieces of a file that changed (not the whole file) are synced. This saves you time.
* Doesn't hog your Internet connection. You can manually set bandwidth limits.
Backup on-line
O Dropbox faz o backup dos seus arquivos on-line sem que você precise pensar sobre isso.
* Automatic backup of your files.
* Undelete files and folders.
* Restore previous versions of your files.
* 30 days of undo history, with unlimited undo available as a paid option.