Also I think Backblaze is geared towards backing up your Desktop with its own client software, or can I use regular scp/ftp/etc(standard transfer utilties) to do my own upload/download?
Backblaze "B2" is a separate service for blob storage with a REST API. It's currently in public beta. I presume its built on the same infrastructure. You can store about 10GB for free if you want to play around with it. (backblaze.com/b2/docs)