Andrew Lipson's Lego Klein BottleAfter seeing some of my other mathematical Lego sculptures, a couple of people asked about a Klein bottle, so... This one hinges open so that you can see its digestive tract. I changed brick colour at the top and bottom to show up the intersection where the tubes cross better. Not because I didn't have enough bricks left in any one colour. Really, honest. Well, OK - it was because I didn't have e
