There are health benefits to the bites of all the scary crawly things.
While the rattlesnake may not be on the list of useful poisons, scorpions are. A scorpion's venom is attracted to cancer cells and, if administered in the correct dosage, has the ability to target cancer cells in the blood stream. Some large medical advances may be locked away in some of earth's deadliest creatures.
Photo (flickr), Creative Common License 2.0, by mikelehen