Always have at least one backup copy that is cold. I'm a big fan of drive docks and using regular internal drives. The way my solution works is all my backup drives have a script on them, so when I insert them and run the backup script on my NAS it will call the script on the drive which in turn runs runs the appropriate backup job script that is on the NAS. So all I really need to do is once in a while, go in my drawer take one of the drives, pop it in, and run the job. The flaw with this is each backup job needs to be smaller than the drives I'm using. As the source data grows I need to adjust accordingly. But it gets the job done for now. I also bring drives to work once in a while to have an offsite backup. At least the most important stuff like pictures and such. I don't really backup my TV shoes and movies and such. I kind of like having them on hand, it's like my own local Netflix, but it also would not be a huge loss if something happened. I actually deleted a lot of TV shows a while back when I was running low on disk space before I did an upgrade.