since it came from here, had to share it !
it's made of kite material and is just for ground display, so that
kids can come to it and kick the crap out of it:
http://mrhide.pinnesota.org/gallery/spike

This is probably not the right place to ask, but I guess it is a good
start.
All of you will i'm sure remember that one of the nicest touches to
the original doom game was the marines "portrait" that appeared on