[Eliot Ness]

I use Excel to keep track of my collection. It comes in handy when I want to see where, when, and from whom I bought a radio from. Since I collect a lot of obscure sets I also make notes about schematics, original manufacturer, etc.

As others have mentioned it's important to backup your hard drives. Personally I use external USB hard drives, but thumb drives, floppy disks or cloud storage also work, as long as you have a backup scheme and stick to a schedule.