Tolkien and European Mythology

[Sulimo]

One of my favorite things about Tolkien was the manner in which he wove together several different European mythologies. Perhaps my favorite was the many embodiments of Odin in his work, such as: Manwe being visited by eagles telling him everything occurring in the world, Gandalf as the gray wanderer, Orome riding his horse, and my personal favorite the eye of Sauron. Which represents the eye that Odin gave up for wisdom. I love this depiction of the ambivalence of Odin, who is represented as both the leader of good and the lord of darkness in these books.

This makes me curious what parallels other people enjoy in Tolkien's work. Please post your favorite parallel.