I just installed a UMPC in my Prius and it uses the car charger for power (it mainly gets its power from it's own battery). I will put windows to sleep when I turn off the Prius. Sometimes, Windows can boot up to install updates from sleep mode. I'm wondering, what happens if it gets stuck while updating...would it drain the Prius battery? How fast?
To my knowledge no 'cigarette lighter' in any Prius is energized when the car is off. Unless you are wiring direct to the harness, you can't drain the battery
If you are referring to using the 'car charger' to mean the electrical outlet (e.g. cigarette lighter socket), it is not powered when the car is off, so this would not affect you at all.
