Jason Criss's knuckles tattoo shows the Enterprise-D from Star Trek: The Next Generation. He writes:
It took me a while to figure out what kind of Star Trek tattoo I wanted to get. I finally decided that the enterprise d on my knuckles was the best choice for me. It’s still a work in progress there will be more shading and colors after the initial outline heals. let me know what you think of them so far.
Note that he can perform a saucer separation by just moving his fists apart.