I'm going to be doing a lot of hours in the air next month and want to make sure I get the most flexible and inexpensive option to keep my notebook alive.

(i) OP above has recommended the Targus Air/Car -> AC 45W inverter for around $35. Alternatively, (ii) one can buy an Air->Car cable converter for $15, and a 140W Car-AC inverter for $22. Finally, (iii) there's Air + Car -> DC converters for around $22, but then you have to buy extra tips if you ever plug in anything aside from your notebook.

My questions are,

(1) Do almost all the airlines offer the same "empower" plug socket in business class (United, Air Canada, Lufthansa...)? I'm afraid to buy a converter only to find that half the airlines use some other kind of socket.

(2) Is 45W enough for a notebook? The Targus would be the most flexible solution, but they don't seem to advertize it as a product suitable for notebooks.
http://www.targus.com/us/product_det...sp?sku=APV08US
My notebook power adaptor appears to be rated at 72 watts but OP suggests notebooks never really need that much anyway.

Otherwise of course, I could buy a AIr/Car cable-converter and a Car/AC power inverter seperately. Option (iii) just seems too fiddly.

Thanks v.much!
starjunkie