The Möbius Bagel...

THIS is how a mathematician slices his bagel!...  ...haven't seen it yet. As you can see above, George Hart (yes, father of YouTube math star Vi Hart ) slices his bagel into two congruent linked halve...  ...- via Krulwich Wonders Oh, George al...

http://www.neatorama.com/2012/11/09/The-Mbius-Bagel/