With the advent of widespread popularity of SuperHeroDom in movies and general culture, many have become familiar with "lesser knowns" of these characters. (indeed - the massive attraction to the superhero architype would be an interesting study from a sociological perspective - is this a felt need? A replacement of God, or a re-packaging of Greco-Roman mythology?)
For many, there seems to be some bizarre delivery of their powers. Through sometimes odd circumstances, normal people wind up with some new or augmented abilities. (if this is reoccuring mythology, the shift seems to have gone from "the gods are like us" to "we are becoming the gods." This too would be an interesting thing to explore, if it's there.) The Hulk, Wolverine, Fantastic 4...etc.
One such transformation that has long puzzled me is Peter Parker into Spider-man.
I am not so much confused by the premise of how he gets his powers, but more so at the tremendously good fortune Peter Parker had in receiving the augmentations/manifestations of spidery attributes that he did.
Consider his gifting: amazing strength and durability, augmented reactions, ability to adhere to and climb walls, webs spinning and his "spidey sense."
Why is it that Peter Parker only gets the good stuff? Consider some of the other possible attributes arachnae; independant mandbiles with poison laden fangs, 8 eyes, complete body hair, 8 seven-jointed legs, and the junk in the trunk: an enormous abdomen.
Similarly, his positive changes could have manifested very differently. What if his durability also came with an exoskeleton? How fortunate for him that his web slinging ability was in his wrists/hands and he doesn't just shoot spiderwebs out of his butt. (imagine him swinging around the city by his butt - doesn't quite inspire the same awe and respect, does it?)
[here I will grant my lack of superhero knowledge and say - I think in the 70's cartoon, he actually had a device that produced the spider silk for him, (market that Peter!) whereas in the recent movies, it was an anatomical feature. Which is true to the original, I do not know. But I do know that the mental image of spiderman swinging around by his butt is a irreducable souce of amusement for me]
So - Peter Parker: most fortunate of superheroes.
Though it's not shown, I'm sure he must have a strong penchant for eating flies.