As a computer tech, I get the question about leaving a computer on all the time, or turning it off. After talking about the power savings, I tell them about the fan bearings vs the light bulb theory. The bearings will wear out quicker with constant use so shutting it off would be netter for that.

The light bulb theory holds that lightbulbs rarely burn out when running constantly (as the one in the Livemore Firehouse). Light bulbs are more prone to burn out when power is switched on, which is due to the temperature of the filiment, resistance being mimimum and current flow being maximum.

I tell them that it is their choice, but with a properly protected computer, it will last longer electronically being on all the time.