Built in Brazil using Volkswagen mechanicals, the X-15 and related G-15 use a Plasteel (steel reinforced fiberglass) chassis. They are 2 wheel drive, were offered in many variants and seem indestructible!
Info: http://www.banovsky.com/archive/gurgel-x15
Portuguese magazine article: http://imgur.com/a/DdCGU
History of Gurgel: http://www.autosavant.com/2009/12/29/genius-or-joker-joao-gurgel-and-the-lost-cars-of-brazil
http://jalopnik.com/gurgel-may-be-the-weirdest-car-company-ever-1441920859
Great info, lousy site (google translate)
More variants (sorry about the mobile link): https://m.facebook.com/GurgelX15/mediaset?album=pb.153587594719517.-2207520000.1433835299
Video:
https://www.youtube.com/watch?v=ayKdJGVG_QE
https://www.youtube.com/watch?v=fUIoo3izAzU
Image credit:
http://www.portaldepiracicaba.com.br/gurgel.htm
http://www.4x4brasil.com.br/forum/jeep-willys/23164-jeep-turbo-na-lama-6.html
https://m.facebook.com/GurgelX15/mediaset?album=pb.153587594719517.-2207520000.1433835299