I like them if they are simple, or a single piece of art, I am not keen to seeing loads where they all merge into one. I have one on my wrist, it has great meaning to me and no-one really notices it, I like it there and look at it regularly and makes me smile. I am in my 40's and only had it done recently.
I've always had a fascination with them, but would not want to cover myself, though I could see how some people would get addicted to getting them.