I have two piercings in my left ear, and three in my right (the third is in the cartiledge at the top of the ear -- at the time, I didn't realize it was supposed to "signify" my sexual orientation, but even if I had known I'm not sure I would have cared).
I don't have any tattoos, but one I've always considered is that of a small gecko on my big toe. (Someone else I knew and admired had the same tattoo, and I just really liked it.) My younger sister has the Chinese symbol for "courage" tattooed in the small of her back (and she knows that that's what the symbol means, because she had a Chinese artist friend design it for her) and is considering getting something else, possibly a Canadian flag. J's parents both have a bunch of tattoos, and his younger sister has the Canadian flag tattooed in the same place that my sister has her "courage" symbol. J and I are the boring ones!
It's not that I don't like tattoos or that I'm afraid of pain. I just can't think of any particular symbol that I value or like enough to have it on me for the rest of my life. Even the gecko tattoo that I like doesn't hold enough personal symbolism for me to want to emblazon myself with it. I don't see piercings as having the same permanency (although sometimes the scarring can ...).