Find in this ring sites academic, photographic, personal and commercial pertaining to the game of marbles, games that use marbles, marbles themselves as toys or objects of art, and the collecting of marbles:  handmade or machine-made, glass (including cat's eyes), agate "aggies" or pottery (including Benningtons), shooters or regular-sized.  Pictured:  some historical marbles from the Cuyahoga Valley National Park.