The vinegaroon or whip scorpion is a relative of the true scorpions and spiders.
Vinegaroons have the large pincers of a scorpion but lack the stinger. Vinegaroons do not produce venom but they can spray an acidic secretion that mostly consist of acetic acid and caprylic acid. The distinctive vinegar smell of the former gives the vinegaroon its name.
Apparently some people like to keep a vinegaroon as a pet.
Thelyphonida on Wikipedia.
YouTube video of a vinegaroon spraying vinegar.