AS3: InteractivePNG
The maker of Fuse, Moses Gunesch, has created a VERY handy little utility class called InteractivePNG that allows you to disable the hit area of a PNG if the pixels are transparent. Simply put, when you save out a PNG that has transparency, rolling over the transparent part of the PNG will still register a roll over because its part of the image. With this class, that is no longer the case. You can read more about it at the link above which should provide you with a way to get the latest version if it is updated in the future.
