Pixen is a sprite art program for Mac OS X by the Open Sword Group, with many unique features not found in any such program on any platform.
Until recently, Mac OS X pixel-pushers have been forced to use a traditional graphics editor in a role for which it wasn't designed; Pixen is the only art program for OS X designed expressly for pixel art. To this end, Pixen features extensive palette management and palette-swapping tools, a highly configurable grid overlay, a full complement of drawing tools, 'crosshairs' for ensuring proportion and straight lines, isometric line locking, extremely configurable backgrounds(for testing a sprite against