Joy as mathematicians discover a new type of pentagon that can cover the plane leaving no gaps and with no overlaps. It becomes only the 15th type of pentagon known that can do this, and the first discovered in 30 years!
Examples of the 14 known types of convex pentagon tilings. Four of the types were found by a homemaker with no education beyond high school. ( http://en.wikipedia.org/wiki/Marjorie_Rice ) Can you find any more?