I keep a working 486 with both 5.25" drive and older 3.1 floppy drives as well as an old 2x CD burner and Dos 6.22. I boot it up once a year to make sure everything still works. It hasn't happened too often, but in the past two years I've had two clients were it's saved their ass.
One was a small company that was still running their entire database off an old 386 box. Eventually it got to the point where their tape drive failed and it was time to move to a new system before they could sell their company and retire. Fortunately the company that created their original software was still around and more than happy to convert the data...IF you could get it to them on an optical disk or external hard drive.
The other time were articles of incorporation and bylaws for another company saved to a 5.25" floppy and again managed to recover and save the data.
I even have a working XT as well, or assume it still works I haven't booted it in probably 5 years.