I'd never have such a specific design done as a permanent tattoo, my taste is always changing, so Id probably regret getting one quite quickly. If I had to get one, it would be a tiny star the size of a mole.
I see it as, i've always loved ninja turtles and transformers. For 19 years of my life i've bought the toys, watched the cartoon, played the games, bought the videos.. bought them again on DVD. As i've got older they were both still a big part of my life (so much so I have the original 4 player turtles arcade machine in my living room), and while at highschool I had to hide my passion from them as of course it wasn't seen as cool or mature. Being an adult now, settled down in my own house with the wife (who can't have a dinning room because of my mini arcade), starting a family I can pretty much do as I please. Of course I still get people saying "do you really want to have them when you are an old man" and I say to them "well if i've liked them for 19 years, 1/3 of my life say, then yes as i'm not a fickle person who will run out and get a tattoo of the latest craze, I only have what I love and holds many memories for me." People seem to think i've had the transformers ones just because of the movies, and I always say to them "i've never even seen the movies".
Rob Westbrook - I too am interested in getting the head of a bull tattooed as I too am Taurus. I had the perfect picture about 5 years ago on a card and since then i've lost it and have never found the same picture again.
If I was going to have a tattoo, it would be of the Pip Boy, but yeah, my taste changes often enough not to really want anything tattooed anywhere.
Disclaimer: Any sarcasm in my posts will not be mentioned as that would ruin the purpose. It is assumed that the reader is intelligent enough to tell the difference between what is sarcasm and what is not.