I made an Ironman suit out of foam and I was told it looked right out of the movies, I had to explain what it was made out of and no one believed me. You know they have the foamies sheet at Michael's and hobby lobby that are sticky back, I wonder if you could print out the pep files of heavy paper and stick it to the foamies and cut it out and fold it so the papers on the inside, i bet that would make it pretty rigid.