I am sure they are only sad, insecure individuals who wish they could be as different as you, but don't have the courage to try or the style and panache to acheive it.
Perhaps as you have said here that you consider yourself to be a freak, you should consider that, like Katie, they are after all only saying that you are so much like yourself. Not much of an insult really when you think of it that way.

It could also be that they are jealous that they are not brave enough or free spirited enough to really, truly be themselves.
Free spirits are always ridiculed by the earth bound, in order to make being earth bound feel less restricting.
Like when you were a child and your parents said that you could not go somewhere you really wanted to go. By saying that you never really wanted to go in the first place, it makes not being able to go much more bearable.
I must admit that my approach to the subject of name calling is a lot like Darksilence's. I know exactly who I am, and they haven't got a clue, so their opinion of me is irrelevant to me. Knowing who you are, admitting to all your failings and recognising your strengths aswell as your weaknesses. Facing your true self without fear, looking at your face without the make up worn for the outside world and accepting all that you are will make you stronger, wiser and better equipped to handle this kind of thing.
If you can face their name calling armed with the truth of who you are they cannot hurt you, because they cannot say anything true that you do not already know, and if it is an untruth what is there to fear?
Change nothing except your knowledge of youself and your attitude to them.
They will not change, but that does not mean that you cannot grow, and leave them behind you.
Shade.