A low cost suggestion. APC makes a power converter that works both in automobiles and airplanes. You plug your powercord into it as opposed to plugging the adapter directly into the laptop. It adds 11ozs. but you can use it for any electrical device. Laptop specific converters run around $100 to $120. The APC device that I bought at Circuit City was $49 with a $10 rebate.
[This message has been edited by Thumper (edited Feb 22, 2004).]