Personally I have a NAS that gets a Time Machine backup every day. I have a handful of important folders on my hard drive that I mirror to the NAS manually (various scheduled solutions have failed me unfortunately). Every few months or so I do some housecleaning and take older projects, personal files off my laptop HD and archive permanently on the backup drive (which is RAID and mirrored)

I have cloud services for anything I share with clients or friends but I honestly don't trust them for anything critical. I actually back up Dropbox to the NAS too. Problem being that the sync strategy across multiple clients can wipe a folder shared between them. It's also a beast to recover from a cloud backup

The trick I'm most proud of is at the end of each year I buy a new external backup drive (now NAS), copy the old one to the new drive, and then label the old drive with the year and store it somewhere safe. It costs a few $$ each year to archive the drives but well worth it - they have saved my butt more than once. I also buy a new laptop workstation every 2 years or so and preemptively migrate everything to the new machine before the old machine dies, and keep the old one around as a spare.