Backup is one of the most obvious uses for cloud computing. A new update to Azure now allows individual Windows 7, 8 and 8. 1 machines to be automatically backed up into Azure.
The backup happens at a scheduled time each day (your machine needs to be on for it to work). The backup option uses an encryption passphrase that is only provided to the end user. If you misplace that phrase, even an Azure administrator won't be able to help you.
Hit the announcement post for more details on how the process works and how to set it up.