After a long stint as a loud and public hypocrite, preaching about off-site backups while not actually having a solid system myself, I finally set up automatic Borg backups through rsync.net. I just set this up last week, and I haven't needed the backups yet (thank God), but so far my experience has been good. My UNIX account was created very quickly after payment and works as expected. Note that there's no complete Bash shell, because they don't want people using a bunch of computational resources or using the servers as a proxy or whatever, but there are a whole bunch of individual shell commands you can use, as well as many backup/data transfer programs. Up and down speed are sufficient for daily backups (though probably not for more time-sensitive things). I had a dumb question about their Borg server that was nevertheless answered courteously and promptly.

Now I have peace of mind about my laptop suddenly dying, which is pretty great.