I've been reading a bit about magic squares. That is, a square consisting of an arrangement of numbers, such that the numbers in all rows, all columns, and both diagonals sum to the same constant.
Probably the most impressive of these has to be Durer's Square, which is shown below:
The orientation of the numbers 1-16 in this square show an amazing about of magic-square-like properties. In total, the addition of the numbers in 86 different spatial orientations add up to 34.