If your dad is anything like mine, "what do you want for Father's Day?" always results in the same, unhelpful answer: Nothing.
No amount of pushing and prodding will lead to a better response, so it's time to take up a new approach: What's an item or experience that could make his [insert activity dad loves here] better? Maybe your dad is an avid golfer who needs a more advanced way to keep track of his game. Or he loves a good road trip, but struggles to find a station that will please everyone.