Materialize is a stand alone tool for creating materials for use in games from images. You can create an entire material from a single image or import the textures you have and generate the textures you need.
AwesomeBump is an open source program designed to generate normal, height, specular or ambient occlusion textures from a single image. Since the image processing is done in 99% on GPU the program runs very fast and all the parameters can be changed in real time.
xNormal is an application to generate normal / ambient occlusion / displacement maps. It can also project the texture of the highpoly model into the lowpoly mesh ( complete texture transfer, even with different topologies ).
Knald is the world’s first GPU powered solution for generating “bake quality” textures from any 2D source texture. Knald generates textures commonly used to create games, like Normal, Derivative, Displacement/Height, Ambient Occlusion, Concavity and Convexity maps.