BMP Grey
AJ Tooth
BMP Grey is a simple freeware tool that generates a grey-scale version as a standard BMP file. This isn't really a mathematical program, but it's useful for swapping the colours around in a bmp file. If you've used "Alt-PrintScreen" to paste a Julia Set picture into a Picture Editor, for example, this program will enable you to change the colours again, in a way a Picture Editor probably will not support.