Well, that's a tricky one, isn't it? Let's see, what does your boss like? Does he have any hobbies or interests that you could use as inspiration? Perhaps you could give him something related to his favorite sports team or a gift card to his favorite restaurant? Or maybe you could think outside the box and get him something that's unique and personal, like a framed photo of the two of you or a special edition book about his favorite topic. The possibilities are endless!