Camel spiders aren’t venomous and don’t really go after humans, but that have been known to chase after them (top speed 10 mph), which is pretty scary. Here's a tidbit from National Geographic:
These hardy desert dwellers boast large, powerful jaws, which can be up to one-third of their body length. They use them to seize their victims and turn them to pulp with a chopping or sawing motion. Camel spiders are not venomous, but they do utilize digestive fluids to liquefy their victims’ flesh, making it easy to suck the remains into their stomachs.
And now there is this video we found from last year, which saw a camel spider take on a scorpion in nasty fight.
