If you haven't begun using the cloud for your sharing and storage needs, its time you started using it. It can be so frustrating when you don't have instant access to something you really need, especially when that thing is digital. After all, we are living in the digital age. When we create an image or document on one computer or device it should be instantaneously accessible on any other device we may use.
Data has always has a portable solution but it has usually involved carrying a physical object to store it (a floppy disk, CD or pen-drive for example). Whilst carrying such an object from one place to another can provide a trustworthy method, there is still a risk the object could break or go missing. This is also true of backing up your personal files onto an external hard-drive; the data is safe if the object is safe.