Here's a thing we came across in our travels today. The X-1 Chameleon mouse from Shogun Bros looks like your standard wireless mouse until you flip it over and discover a complete gamepad underneath. The mouse switches between its standard function and the controller (as well as a "presenter mode" for those who have grown-up crap to do with their mice) at the push of a button and features two analog sticks, eight buttons, and a directional pad.
The mouse operates on a single AA battery with support for a rechargeable battery via USB and features a 1600dpi laser. I picked one up and fiddled with it a bit and found the buttons to be a little bit on the spongy side, which would lead me to have some concerns about accuracy. But as a guy who likes to be able to whip out a controller at any time, this might make a very helpful travel companion on trips like this.
The Chameleon X-1 is currently for sale over on Amazon, where it will run you $59.99 and is available in three colors, while a fourth (white) seems currently absent.