Creating hollow objects

Hi there,
I have bought this program called Stella4d which exports dxf polyhedron files (cubes, icosahedrons, etc).
I am going to print a bunch with a 3d printer, but to save money on materials I want to hollow all of them out with blender.

I am hoping to achieve something similar to this.
http://internationaldisplays.co.uk/images2/products/OpenCube1.jpg

My only problem is that i will eventually be dealing with objects with very complex faces, so i cannot build each polyhedron from scratch.
I am hoping to use the dxf files to my advantage.

Thanks

Mesh -> Scripts -> Solidify Selection ?

Or model it yourself:

  1. Extrude Region (E > 1 > Enter)
  2. Shrink/Flatten (Atl+S) to 0.2