3 links have been added on this idea.
  1. And why not have huge pool tables on crazy golf courses? I played on one once and it was tricky to pot anything but with bigger pockets and balls it would have been loads of fun. Found a pic of one too, see the link https://www.pinterest.co.uk/pin/766878642771768074/

  2. Often thought of this but never found anything that isn’t flat. Everything they have is missing a whole dimension of fun. Especially if you could stick magnets to the underside and reinvent the game each time you play.