if you dont *need* it to animate into being open: take a sheet of paper fold it on various ways but dont allow it to go too flat, scan it (again dont squash it with the scanner´s cap but put another sheet over it) cut n paste the resulting grayscale image and photoshop adjust it into being your bumpmap for a simple cube

make the ribbon with curves and extrudes

uh... just for fun a ctulhian tentacle going out from the bottom of the box is always a nice touch