High Velocity Experiment: Toothbrush
The following experiment was completed by dipping a toothbrush into whole human blood and flicked with the thumb onto a vertical cardboard surface. I personally don't know of any cases where a subject was running around creating bloodstains with a toothbrush. This experiment was done to demonstrate the amount of force that was applied as well as the small surface area (bristles) that the blood had to accumulate on.
The mechanism (used for experiments only). :)