I saw a post on in this N scale forum which spoke of Z scale. If you think Z is small, apparently there are 1:900 trains. (This is NOT a joke - although I think you would go blind trying to work on them.) See: http://dfwtrains.tripod.com/DFWtrains/id10.html or go to: http://www.lilliputmotorcompany.com/index_frm.html (At this second link, click on "Toy Trains" and then when you get to the "Toy Train" page, scroll down about half way.) Regards!