This is my attempt to break up 3d Hub's Marvin to make dual colors.
Please note that by very simple editing of the scad file you could choose to include different body/suit parts in each stl for different multicolor desires. See instructions or scad comments for further details.
By editing the single vector at the top of the attached .scad file you can customize which of the follow body elements are in your stl: legs, helmet, head, ear cylinders, ear hemispheres, @ keychain loop. Once you've exported the first file, change "Nozzle" to 2 and export again for the complimentary body elements.
Want the legs to match the face, but not the helmet? Done. Both ear pieces the same color? Easy peasy.
Thanks to no error checking you can also remove a body component entirely. Mark that element as "2" in the vector and it will not show up in either stl (I'm looking at you keychain loop). It's a feature ;-).