Since my first year of teaching I have kept a paper gradebook. I did use spreadsheets for my calculations just to make that aspect easier, but even when my school districts moved to online recording systems, I still maintained a paper copy as my primary means of recording attendance and grades. In particular, I used the Whaley three-line gradebook as it allowed me to keep grades, attendance, and behavior all together. In a couple of instances, including a complete system wipe, having the paper gradebook as a backup (although it really was my primary) saved me from a great deal of heartache.
However, technology has improved a great deal since that last crash and keeping the second book was becoming more of a burden than a benefit. Last year, I largely used the book to keep track of attendance as I got into the habit of entering my grades directly into the computer (instead of into the book and then into the computer). It seemed like a good time to let go.
I still have a couple of blank Whaley gradebooks just in case.