The tarantula hawk is neither a tarantula nor a hawk -- it's a very big, very mean desert wasp. And of course someone on the internet decided to get stung by one.
Oddly, the tarantula hawk isn't a particularly aggressive insect. Generally they buzz around, eating nectar and avoiding humans or other animals. It's even the state insect of New Mexico. The thought of friendly, brightly coloured bugs peacefully humming around cacti almost makes up for their horrifying reproductive cycle.
A quarter inch long, the female's stinger is vital to the process of making more tarantula hawks. The sting itself -- which is one of the few to rank as a 4 on the Schmidt sting pain index -- is used to paralyse an unsuspecting tarantula so that an egg can be laid inside its body. As it grows it eats away the spider's organs until bursting out Alien-style to begin the process anew. Unsurprisingly, a sting that can make a spider unable to fend off its new job as a living womb is enough to impart excruciating pain on a human.
Thankfully, that pain only lasts about 5 minutes, but it looks to be a very, very long 5 minutes.