Cool replies guys, i'm investigating the suggestions given. A couple of details:
My gopro is indeed based on SD cards but my camera (canon 7D) uses CF cards, so i would have to use a usb based external card reader any way.
On my last trip the amount of collected data was over 350GB (time-lapse photography and movies take up a lot of space ;) )
I do have a connection to my NAS from anywhere in the world and when i have the chance to get a solid internet connection i could take advantage of that for some of it but i would like to set up a "in the middle of nowhere" scenario and see what my options would be worse case :)