From what I have seen on-line, one method to get an object textured as desired is to create a separate material for each face of the object and apply a unique texture to each face.
For example if you wanted to create a dice without a UV mapped texture to hand, you could simply use a cube, get images for each of the 6 sides and apply those images to each side of the dice. The alternative as I understand it, is to export a UV outline to GIMP or photoshop and remember which way is up for each side of the dice and construct a single texture.
So my question is, is it possible for blender to project the final objects textures (you created using multiple materials) onto a flat UV mapped surface so that you can then save that texture and apply it as a single texture to a new cube later?
Essentially going from a complete 3D object using multiple textures, to a complete 3D object using a single texture.