There is always someone on your gift list that is "hard to buy for". I have a solution... pillows and pillow cases. Everyone uses pillows. Even a teenager who seems impossible is usually in to something (skateboards, hot peppers, sports, dance,science, etc.) that you can find on a printed fabric. Then you transform that fabric into a throw pillow or a pillow case with a new bed pillow and you have a prized gift in no time.
My grandmother loved satin pillow cases. She swore that her hair stayed better than with a regular pillow case. It's never worked for me but many people swear by a nice satin pillowcase. Finding them to buy one is not as easy as making one in a favorite color.