Dual Extrusion Voronoi Duck
This is a Voronoi duck with two shells/solids. It could be used for dual extrusion or 2-color printing. I have no experience with this yet so I uploaded the two separate solids and the combined mesh (with two solids).
I used www.voronator.com to generate a Voronoi mesh, check it out - it's a free online tool!
I used MeshMixer to align the Voronoi mesh to the original mesh with the ''Align to target'' tool. Check this MeshMixer manual website for more info: http://www.mmmanual.com/edit-align-to-target/