I would venture to say that most people have noticed the tattoos on people of all walks of life.
Although I personally find them distasteful, maybe due to my age (73), I must admit that some of them actually are quite fasinating. They come in all sizes and shapes. Most of the ones that people see are done by persons that work/own a tattoo studio. These tattoos are brightly colored and depict such innocuous things such as flowers, animales, fruits, etc.
The tattoos that I want to talk about are not so innocuous, in fact they are quite harmful and even deadly, if used by those non-members of various prison gangs, outlaw motorcyle gangs etc.
I remember receiving word from a CDC (Cal.Dept.of Corrections) employee that said that a new inmate was received at Folsom Prison in the early 1970's wearing the emblem of the prison gang known as the Aryan Brotherhood. The inmate was held down by several AB members while one used a sharp shank to cut the tattoo of his chest. Most prison gangs take it personal when a non member takes it upon himself to use what they consider a copy righted symbol.
It is easy for the trained eye, (especially a gang officer) to distinguish a prison tattoo from a free world tattoo. Most of those older and some newer prison tattoos are made with Indian Ink using any kind of pin or needle to penetrate the skin. Over the years there have been ex-cons and
street gang members afflicted with the hepititus C virus. (This virus attacks the liver and can cause death.)
Here are just a few examples of weird places on the body that I have witnessed or have been told to me by reliable persons:
On the inside of the lower lip; behind the ears; on the neck; on the ear lobe; between the fingers; on the top of the head; and the best (worse one), was on the penis of an old time Mexican Mafia member who was recently murdered in a bar. This was discovered by a policeman who was booking the member in on a narcotics charge.
I am sure there are many other places but these are the ones that I know about.