I wonder if something like this Mili Power Crystal External Power for Digital Devices w/6 Tips, Black HB-A10-BC (http://www.cyberguys.com/product-det...CH#page=page-1) would work? Unless the PE can be powered through its mini-USB port I don't think this is exactly right, but the idea seems good to me.

Haven't the airlines gotten around to providing power outlets yet??

If I see something that will work for sure, I'll let you know. Meanwhile, happy travelling!