A lot of my files and some of my data live on the cloud, which is more or less de-facto off-site backup. However because most cloud-based solutions exist to provide real-time synchronisation actually relying on cloud storage as a real backup solution is unworkable. The data is too vulnerable to accidental loss which will propagate across devices rapidly and likely irreversibly. There's a lot that isn't covered too, and therefore a thorough off-site backup is still a sensible thing to have.
The traditional method is to physically move backup media to somewhere else, for recovery in case of emergency. It seems silly though to go to all that effort when the technologies that power cloud solutions can as easily be employed to hold true backups at some remote location on your behalf. There are in fact a number of services out there that provide this kind of backup facility. These solutions are primarily subscription based and you have to trust another entity with your data (and potentially another government). So I've been looking at some manner of private cloud hosting.
So far I'm most interested by Transporter which allows you to create a small private cloud of your own or with family or friends. Ideally I'd want something that will allow me to configure Time Machine to target the disk, which would then alternate between backing up locally to my Time Capsule and the Transporter disk. I'm not yet sure that this would be possible without also having to maintain a local copy of the backup which would be undesirable. In theory collaboration with a group of friends would allow for distributed off-site backup for the everyone involved.