Felix made some interesting observations with his post. Regarding the "impossible" or should I say "impractical" checkmates in the corner other than the one of the Bishop's color -- true it is that in real live play they would most likely not occur against a strong human. However, from the perspective of the computer, they must be solved, of course! While the mate in 1 scenario can be recognized, I could post the most distant win where it spirals into such a checkmate, and even from a few moves away the solution might not be readily apparent to a human. I mention this because a computer will always find the QUICKEST path to a victory. If the human player makes an imprecise move, the program will not care a whit about whether to force the knight mate or chase the king into the correct corner with the bishop (a much longer task, usually.)

So, should a human make one miscue, he could find himself embarrased at being mated by the knight!

I had not made Felix's observations about the Bishop color -- that the database switched colors and generated a whole class of mates that are otherwise virtually identical! I will have to consider this as I compress the database and make it available for others when I write the program to probe it.

Currently, there are two files, a white to move file, and a black to move file. Each one is over 36 megabytes, but I can reduce it by more than a factor of 4 when I create a better indexing scheme.