They run 10 mph, jump three feet, are a nocturnal spider, so only come
 out at night unless they are in shade. When they bite you, you are
 injected with Novocain so you go numb instantly. You don't even know you
 are bitten when you are sleeping, so you wake up with part of your leg
 or arm missing  because it has been gnawing on it all night long. If you are walking
 around and you bump something that is casting a shadow over it, and the
 sun makes contact with it, you better run. It will instantly run for
 your shadow, and scream the whole time it is chasing you.
 PS. The one on the bottom is eating the one on the top. These are
 Spiders found daily in IRAQ by troops. Imagine waking up and seeing one
 of these in your tent!!