Hey dol! Merry dol! Get lost Tom!!!

[Inziladun]

One thing I really like about Bombadil is his air of mystery. Even the usually highly knowledgeable Elves, for example Elrond and Glorfindel, don't seem to have a lot of firm data about him. That despite his being around for many ages.

Also, I think of Tom as an "anti-Sauron", of sorts. Unlike the latter, completely consumed by a desire to control all Middle-earth, Tom is content to stay is his own little area, and to be left to his own devices. I've always found a striking illustration of the contrast between Tom and Sauron when Frodo gives Bombadil the Ring.

Then suddenly he put [the Ring] to his eye and laughed. For a second the hobbits had a vision, both comical and alarming, of his bright blue eye gleaming through a circle of gold.

Tom's blue eye, as opposed to the Red Eye of Sauron. I think that's quite interesting, and not merely a throwaway bit of detail on the part of the author.