Carbon Copy Cloner 5
As a part of my switch to using iCloud Photo Library, I decided I wanted to have a direct clone of my Mac (on top of Time Machine and Backblaze), so I decided to pick up Carbon Copy Cloner 5.
This newest version is ready for macOS High Sierra (and the new APFS file format). Version 5 includes Task Groups, a Smarter SafetyNet, Guided Restore, new scheduling options, and much more. You might be wondering you'd want a direct clone of your mac's hard drive? While Time Machine makes great backups, it cannot be booted from. In a pinch, you could boot from an external drive to get back to your data very quickly. I find it to be a useful part of a 3-2-1 backup strategy (3 copies, 2 formats, and 1 offsite).
If you have used CCC previously, learn more about the newest features.
You can buy Carbon Copy Cloner 5 for $39.99. If you have a previous version, you can upgrade for 50% off. There is also a 30 day free trial.