This is great! DS9 was/is obsessed with maps too. We have maps of the world and the US on his walls, when we travel he collects maps from our stops, at amusement parks he gathers the maps up and memorizes them, a favorite toy when he was little was the Leap Frog Globe, he will pore over street maps, and family members send him maps from their travels as souveniers!
We don't have an obsession with pencils or calculators, but there is a strong preference for mechanical ones. Although, if given the choice I don't think DS would write at all. He can't wait for the day he doesn't have to handwrite anything and it's all on computers.
