I like the look of certain tattoos. Some people definitely have better ideas than others as far as what would be good to permanently ink into your skin. Personally, I will probably never get a tattoo, mostly because I would regret it as soon as it was finished.
I think if you can get yourself something that means something to you, a tattoo is a good idea.
I think if the tattoo shop is having a sale, you shouldn't just get a tattoo because the shop is having a sale (I only say this because my sister got a rinky little tat of a lucky cat on the back of her neck on Friday the 13th just because they were only 13 dollars -_-).