Tattoos

What are the purpose of tattoos? Why do people get them? It seems that more and more people are getting them. What is this all about?
The purpose of a sign is to communicate something. What is being communicated.
In past generations you would only think of military men getting a tattoo to mark their belonging to a certain branch.
I tend to think of tattoos as a grasping for significance in one's life. I want my life to mean something. I want my body to indicate some reality that is greater.
In baptism we are marked by the sign of the cross. For the Christian this mark of baptism gives significance to our bodies and to our souls. The body of the Christian is a 'Temple of the Holy Spirit.' If this Christian awareness exists in a person then their is no need for other markings on the body.
It seems to me that the modern person, for whom this Christian awareness does not exist, is grasping to express a sacramental reality.