Tony --

Well, sort of, but not quite. I'm not warming the empeg to 100 degrees -- I'm warming the air beneath it. And not for a few minutes, but for three to six hours. It's not like I'm going to be taking a hair dryer and blasting away.... it'll be more like the effect you would get by placing a 40 watt light bulb three inches below the empeg and switching it off every time the air surrounding it got over 100 degrees. I don't intend for the empeg itself to ever reach an internal temperature of more than 50-60 degrees. It will take a little bit of experimenting to find the right thermostat setting to achieve that goal.

Your point about repetitive temperature cycling is a good one, though... I just don't know what the effects of large temperature swings while the unit is turned off will be. None of the other electronics in my car seem to mind it (CD player, engine management computer, etc.) and they get fired up every morning stone cold. So any problems might center around the hard drives, and the whole objective of this plan is to have them at a normal operating temperature before they are turned on. Also, keep in mind that while the temperature swings are large, they are NOT rapid.

Anybody have any experience with laptop computers and large temperature swings?

tanstaafl.

"There Ain't No Such Thing As A Free Lunch"