>This kind of application is really better suited for thin, light servers that you keep on your home network. Especially when you store large media files such as movies and music. Storage is really cheap at home, just connect as many sata-disks as you'd like.
I couldn't disagree more.
This is exactly the kind of project which is least suited to storage on a home network; the appeal of cloud-storage is that it's always available, from anywhere, even if your house is struck by lightning while burning down, *and* you don't have to maintain your own server infrastructure.