We're not saying they're all good, but at least they're different,
With everyone and their mom getting tattooed, it's hard to look different. Tattoos are no longer quite the unique identifier they were for the 20th century (and beginning of the 21st), particularly because so many people get very similar designs and styles.
In most areas, you'll be able to find someone who specializes in American traditional or neotraditional tattooing, an artist who focuses on fine line black and gray pieces, and at least one person who claims to be well-rounded enough to do just about any style (and who'll happily do the infinity sign on your wrist or simple skull on the outside of your upper arm). In cities and towns with at least a handful of shops, you can probably get some good color realism work done, plenty of cartoon-y illustrative ink, and a Japanese sleeve or two from the artists around.
Then, there are some styles and methods of tattooing that you don't see everyday. Some are trendy, some have been around for centuries, and some make it damn near impossible to find an artist who really knows what they're doing. Here are five "other" styles of tattooing, if you're not looking for a basic portrait or a Sailor Jerry-esque design.
Scrimshaw
If you're just talking about scrimshaw as an art form, then you're discussing the bone designs that started being done on whaling ships in the mid-1700s. As for the tattoos based on that art, scrimshaw tattooing is a staple of many blackwork artists' portfolios. Done without color and in the theme of what might've been etched into a whale bone centuries ago, scrimshaw tattoos are more popular than they have been in the past, particularly for those looking for something a little different and rugged.
Biomechanical
Although biomechanical tattooing has been around for quite some time, it's only really found a life of its own during the recent boom in the popularity of tattoos. World-class artists like Roman Abrego are bringing biomech to levels it's never seen before, incorporating everything from classic gears to futuristic and alien parts. If you want to make one of your limbs look robotic without actually having any surgery, it's a better time than ever.
Tatau/Tebori
For the true tattoo collectors, anthropologists, and historians out there, getting inked by an artist using a machine can get old. That's where the truly old-school methods come into play, such as the Polynesian tatau and Japanese tebori techniques, both of which are done using large handheld needles to inject the ink one bit at a time. Obviously, such methods require highly trained professionals, but those who have mastered them can create amazing pieces on anyone brave and lucky enough to get one.
Trash Polka
While trash polka tattoos haven't become quite as popular in America as they are in Europe just yet, they may very well be the next trend to take over the industry. Over the last few years, the style has evolved from a hokey gimmick to a legitimate art form coveted by many. It fuses detailed black and gray images (typically of vintage, industrial, and dark designs) with red paint-like accents and newspaper-esque fonts. There's something about them that feels very V For Vendetta.
Watercolor
Go ahead and ask your favorite tattooer what the worst trend in tattooing is these days. Odds are, they'll say something about watercolor tattoos. Although tattoos are primarily subjective and you shouldn't avoid getting a tattoo simply because someone else thinks it's dumb, watercolor tattoos aren't known for holding up terribly well over time, and they tend to come in and out of fashion quite often. Maybe rethink that watercolor butterfly you were going to get in the middle of your chest.