Methods, systems, and apparatuses, including computer programs encoded on a computer storage medium, for optimizing search engine user input selection are disclosed. For example, the trifocal pattern can provide near, far, and intermediate foci such that the near and far foci are substantially coincident, respectively, with a near and a far focus of the bifocal pattern. The preferred embodiment of the drum pillow is used to deaden or modify the sound, esp. These cavities may be configured to catch forward-moving energy of water moving forward relative to the board, while allowing passage of rearward-moving energy of water moving rearward relative to the board.