CRIME SCENE RUG

Found via Oddee, picture via Lazy Bones
You can turn any place into a crime scene with this portable Crime Scene Rug sold by Lazy Bones, a UK based novelty company,  for what would be around $20 USD plus shipping and handling.  

It even comes with its own attachable/detachable Velcro handle for carrying and storing so all you have to do is roll it up and go.