I have a hereditary mole on my right leg, not sure if that counts, but I thought it was awesome (my older brother has it, and my mom has it, same place. My older sister has it on her left leg.)
I also have a white spot in my hair. I also had another hereditary mole, it was on the left side of my head, but it got shaved off on accident when I was 9, and now white hair grows from that too.
Thats about all on my side. Tell about your interesting (or boring) birthmarks!