At Main Screen (Team select), just press 1, 2, 1, 2, SHIFT CTRL.
Hidden Stadiums:
At Main Screen press 1, 2, 1, 2, CTRL, 2, 1.
Automatic mammoth home run:
When the player information box comes up, type in and hold 1, 2, 3, 4
then press Up, Space, Left, Right, Shift, Alt, Down, Ctrl.
Automatic strike out:
If the batter misses the first pitch, type, and hold 1, 2, 3, 4
then press Ctrl, Down, Alt, Shift, Right, Left, Space, Up.