Alien Life on Earth - Flannel Moth and moreWhat happens when you take the worst part of a bee and multiply it a thousand times?Alien Life on Earth - Flannel Moth and more by Malicious-Monkey
And no, this isn't a wasp with an unusually long stinger. We'll save that one for later.
Every hair on the flannel moth larva is filled with venom. This particular caterpillar will only cause irritation, but others like it can be much, much worse. While some of them look like the works of Giger, most are fuzzy, beautiful, and quite tempting to pet. My advice: don't. Here are some particularly nasty examples, and the symptoms they cause.
Bag shelter caterpillar: death by hemorrhaging
Saddleback: rash and swelling
Puss caterpillar, the one that spits acid (this is the same as the flannel moth)
And more: http://www.environmentalgraffiti.com/nature/news-ten-creepy-and-colorful-caterpillar-hazardous-human-health?image=0