A friend is someone who is always there for you no matter what. They will be completely honest with you and criticise your weaknesses but compliment you on your strengths. They will share their most intimate thoughts with you and listen to yours e.t.c. A best friend usually shares the same interests as you so if your a tattoo enthusiast and your friend is too then why not consider having a friendship tattoo? Same principle as a friendship band but a tattoo is for life just like your friendship. An idea for a tattoo would be friendship band but designed to be an actual tattoo. There is some reference for ideas and inspiration for friendship tattoos but not as much as I would like. But I guess in order to find the perfect friendship tattoo you really need to look to yourself for the inspiration. What are your interests and what styles do you like e.t.c. Where do you plan on having the tattoo, on your ankle, wrist, upper arm e.t.c. Would you both be getting the same tattoo? A good idea would be to have the same tattoo but in two halves, similar idea to the broken heart neck chains you get.