Enter the Matrix: Some of you may not be mathematics morons of my level, but this boggles my mind:

Since the time of Descartes, we've found it very powerful to label points by their coordinates, either on Earth by their latitude and longitude or in three-space by the three Cartesian coordinates, x, y and z, that you learn in high school. And we've always imagined that those numbers are like ordinary numbers, which have the property that, when you multiply them together--which is often an operation you need to do in physics--the answer doesn't depend on the order of operation: 3 times 5 is 5 times 3. What we seem to be finding is that when you coordinatize space on very small scales, the numbers involved are not like 3's and 5's, which don't depend upon the order in which they're multiplied. There's a new class of numbers that do depend on the order of multiplication.

They're actually not that new, because for a long time we have known of an entity called the matrix. Sure as shooting, matrix multiplication depends upon the order of multiplication. A times B does not equal B times A if A and B are matrices.

Thanks to that link from A&LD, I now need a beer.