Daisuke Matsuzaka was interviewed at the WBC and was vague (intentionally maybe) about the gyroball. He said he was 'trying to develop' the gyroball and had 'thrown it once or twice'. It honestly sounds very similar to a Greg Maddux pitch in that it's not a breaking pitch as far as the arm wear and tear go since the spin is imparted by the standard pitching motion, grip and follow-through. It sounds like it's a difficult pitch to have a good feel for as well...it's something that you or I could go out and try to throw and get absolutely no movement. I've tried this by the way and I couldn't get it to move at all...then again my dropball (basically a slurve with a different grip) that used to move a bit over a foot when I played was only moving about 6 inches when I went out and tried it so that could just be my own lack of pitching ability.
Oh, and while it is just a variation of the eephus pitch Casey Fossum gets a big
for naming one of his pitches after himself - The Fossum Flip. I LOVE watching when he's on and he whips out the Fossum Flip and deals at about 45-50 mph...that's just sick how badly he gets the batters out in front.