I have this box.net account with 50GB free space unused. As Box supports DAV, we can mount it as backup storage. Below lists the commands to get you there.
$ sudo apt-get install davfs2 #assume you don't have davfs2 installed yet
$ sudo mkdir /media/box.net
$ mount -t davfs https://www.box.net/nav /media/box.net #you will be prompted for username and password
$ ls -l /media/box.net #list your box.net folders
# sudo vi /etc/davfs2/secrets #add below line
https://www.box.net/nav username password
$ sudo vi /etc/fstab #add below line
LABEL=BOX.NET https://www.box.net/dav /media/box.net davfs rw,user,auto,_netdev 0 0
$ sudo mkdir /media/box.net
$ mount -t davfs https://www.box.net/nav /media/box.net #you will be prompted for username and password
$ ls -l /media/box.net #list your box.net folders
# sudo vi /etc/davfs2/secrets #add below line
https://www.box.net/nav username password
$ sudo vi /etc/fstab #add below line
LABEL=BOX.NET https://www.box.net/dav /media/box.net davfs rw,user,auto,_netdev 0 0
