I did a little research lately into the mythology of the Gorgons (you know, the group Medusa belonged to) and came across some interesting little facts.
(1) Some researchers believe the Medusa character was based on a queen of amazon-like warriors from North Africa. (Medusa is derived from the greek word "medea" which means something like "queen"). Although Medusa was mortal, her two sisters/counterparts Sthen(n)o and Euryale were immortal.
(2) Some poets treat them as gods, others as spirits, others as monsters (much like the Erinyes, or "Furies.")
(3) Gorgon means "terrible" and (I think) is the root word for Gorgias (the ancient Greek sophist who Socrates repeatedly bested in Plato's Socratic Dialogues.)
(4) A Gorgon would "petrify" their victims with their gruesome faces, but could not be petrified by seeing their own. Although Perseus uses a polished shield to defeat Medusa, it is only used to reflect her visage so he does not have to look at her directly. Even the movie "Clash of the Titans" adhered to that aspect of the myth (the origin of that mechanical owl? beats the crap out of me--probably something Hephaestus made for Athena or something...) I believe that aspect of the mythology was actually (erroneously) altered by none other than E. Gary Gygax in the Monster Manual.