How do you crash a computer? Answered
Using any common household technology, how can one create a compact device that can crash a computer without actually doing anything to software. hardware crash. idk magnetic fields, large electric currents? something hand-held preferably. Safe to hold not safe to a computer within a few inches.
Update: You are all right, a reversible device is best, but not completely, as in wipes all memory but the computer is not actually destroyed so can still function with a new OS installed