Travel Technology - Inflight power for laptops over 75w

I have a Macbook Pro 17in. I know it's pretty silly for travel, but I am a graphic designer and need it for power and screen size.

I was on the United p.s from LAX-JFK a couple weeks ago and my laptop kept tripping the circuit because it requires more than the alloted 75w.

I have been reading around and saw that there are some Power inverters such as this one here that might work:

http://www.apc.com/resource/include/techspec_index.cfm?base_sku=PNOTEAC150A

I was wondering if anyone had used one of these with a laptop requiring more than 75w?

Thanks in advance!

Those won't work either, because they draw current on the AC side based on the demand on the DC side; so if your macbook pulls 90watts, this thing will pull the required amount out of empower... AC/DC inverters actually pull even more because their conversion loses a lot of power. The only option I can think of is to turn the machine off and let it recharge off empower, charging doesn't pull as much as charging AND powering off empower.

or take the battery out to eliminate a charging drain.

Also empty the CD/DVD. It seems to use a lot of power when spinning.

Lowering the screen brightness might help a little bit.

And be sure to turn off the AirPort (wi-fi). Aside from the airline rules about that, it draws power.

All good tips. Thanks!