When it comes to cool tattoo ideas you can't get much cooler than Japanese. Japanese tattoos can be called irezumi or more correctly horimono and are often very colorful and highly detailed. Getting a good one pretty much guarantees kudos from people due to their exotic origin and great design.
1. Koi - Nishikigoi
Now you may think it odd to have a fish tattooed onto your body but in Japan these fish are considered to be living ornaments and if you see some of them you'd have to agree. These tattoos are often done swirling in a mass of colorful waves.
2. Geisha
Geisha women train from an early age to be perfect entertainers and hosts to their guests. Mastering skills such as music, art, dance and much more over many years. Their style of dress and make up is famous the world over and a traditional geisha tattoo done well can look incredible. The key with geisha is subtlety. Avoid going for something excessive and over the top as you'll be a laughing stock if you have a geisha riding a dragon firing ice arrows.
3. Anime
Anime is everywhere in the US with a never-ending stream of fans and artists. Not only are they cool - they never fall out of fashion. You could get a character designed for you or choose one of the many already in existence. Akira perhaps? Be careful not to choose something too popular though as you'll risk looking like every other anime obsessed fanatic out there. Most tattoo studios have someone capable of producing good quality anime designs from scratch so check out your local studio to get ideas on anime designs.
4. Dragons
One of the most popular forms of tattoos is the Japanese dragon. Which is understandable considering the powerful look of the beasts and the huge range of possibilities available. Green, red, yellow, blue, black and everything in between with great detail throughout. Be sure to research dragon tattoos thoroughly though as certain aspects can have specific meanings. Such as the number of 'fingers' on the claws or the color of the dragon. The last thing you want is a dragon that represents female fertility.