I work at Sun Microsystems.
The opinions expressed here are my own,
and neither Sun nor any other party necessarily
agrees with them.
Some airlines have these weird little special sockets that you can use to power your laptop, if you have the right adapter cord. They work OK. Twice in the last couple of weeks I’ve got on an Air Canada flight, both Airbuses (a 319 and a 321) and found an ordinary 110-volt 3-prong plug in the seat-back in front of me. All airplanes should have these.