Tattoos like just about anything else fall subject to experimentation and trends. One area which is an overlap of the two concepts is the black light tattoo. I'll tell you straight off the bat: you probably shouldn't run right out and get one of these, no matter how cool you think it is.
The idea of having something in your skin that glows under special light has a distinctive appeal to some people. However this is one of those areas where the latest science isn't developed enough yet to have gotten ahead of the desire. At the present time, too many people who are pursuing this idea of body art are winding up with medical problems.
Outside the spectrum of normal human sight is the ultraviolet or black light range. Under this purple-looking light, certain colors will glow, most notably optically-brightened white clothing. Black light ink will look like a normal colored or even blank spot in a tattoo, and then fluoresce under the appropriate lighting. Inks have been produced which have passed all of the FDA steps to be marketed, and yet, black light ink causes more adverse reactions than any other color of tattoo ink.
Interestingly, many people tattooed with black light ink are fine at first. However, if you do some digging around on tattoo and body art forums and blogs, you find that months afterwards or even a year later, lots of people are having the areas with the black light ink become puffy and red. So far, the only way to fix this unhappy tattoo patch seems to be to tattoo over the black light ink solidly with black. Many designs will not look anything the same with large areas all filled in with black.
No word yet on if laser removal has any effect on black light ink, but since regular pigments respond due to what wavelengths they can absorb, most likely there isn't a laser yet that can safely "zap" the black light ink without causing skin damage. There's also a lot of debate about how bright these inks really are, and whether or not they stay bright over time. Anecdotally, it would seem that there is a significant drop-off in brightness, but how much or how fast isn't consistent from person to person.