I've shared a 400 W inverter with my brother a few times on long car trips; me with either a 15" 500 MHz Ti or a 17" 1 GHz Al; he has a PowerBook G3. My mom's Dell laptop would kill the inverter, though. ;-) You probably want to get something that's rated well over what you plan to use, though; your PowerBook will draw up to 65 W, maybe slightly more even. If you want to use anything else, add its wattage, and then bump it up some. If you only want your PowerBook, a 100W inverter should handle it just fine. YMMV Anna Dembska <anna at fleap.com> writes: > Does anyone have any experience using an inverter or converter with a > cigarette-lighter end to plug the standard power supply into a car or > battery pack? There are 75- 175 watt inverters available from Belkin > and others for about $30. I'm trying to decide if I can buy one of > these or if I have to get the auto power supply. > > I have an 867MHz 15 inch titanium powerbook.