So I'm looking at starting a helmet project with the good ole' pepakura halo helmets, but taking it a step further. Essentially what I am wondering is how one would go about adding some protective foam or padding that can absorb impact (I'm talking motorcycle grade here). The design I'm looking at calls for some custom work, otherwise I'd just gut an existing helmet off the shelf. Does anyone have any ideas on accomplishing this? I'm thinking the helmet shell will be carbon fiber for added durability so I'm hoping to get some feedback on what everyone thinks would be the best protective layer for the inside. Also, please no "For your own safety just buy a helmet and don't worry about the looks" This is a novelty just for fun, but I'd like to know I could use it if I wanted to. Let me know what you think!