I came across this video today on Yahoo and it has some very helpful advice.
It includes solutions to these problems:
Touchscreens that won't work with your gloves on
Dirty cell phone cases
When gadgets get wet
Scratched cd's or dvd's
PC's that sign you out too quickly
Don't have enough D batteries for your flashlight
There are some pretty cool solutions here. When I used to work for Verizon we suggested the dry rice with the phones and that does work.