The only damage would be to the battery. The hardware should see negligible wear due to just that.
Interesting thought though. I really wouldn't need the screen on all the time...
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HS visor Deluxe (Blue) & Palm IIIx -> HS visor Prism & treoPhone ->
P1 T|T & SE T68i-> Tapwave Zodiac2 + P1 Treo 650 GSM -> Treo 680 unlocked -> Pre Sprint
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