Running a Server at Freezing Temperatures?

mw13068 asks: "As a part of a backup solution, I'm thinking of running a backup server in my unheated, unattached garage. I live in central New York State, and the temperatures very often drop below zero degrees Celsius. The computer is a Pentium III Celeron running at 733MHz. Has anyone else tried this sort of thing? If you have, please share your experiences."