Sprite Monkey

how cool is this? and it's for the mac! kinda rare i think. they even provide a kickass tutorial video about how to design your sprites for the sprite sheet/strip -- very neat, especially if you are making a 2d platformer for the first time.

Sprite Monkey is the smallest and fastest sprite editor without sacrificing features! Quickly edit your sprite sheet/strip, aka “texture atlas”, in a simple uncluttered user interface. Easily create sprite coordinate scripts in the “no plugin” script editor for any game engine or programming language. Export custom PNG images not found in other editors for a smaller file size