I have made a small gimp script last year to make good quality normal maps from photos similar to what crazy bump does. I expanded on it and now it has a real time viewer with "realtime tweaking" and the ability to generate diffuse(seamless and with filters to remove low frequency shadows), spec, normal and AO maps. I reported it back to windows so a greater number of people can test it.
Here are some screens of the GUI and the results.
A realtime scene in blender with maps made with Insane Bump
If anyone is interested i can release the installer for testing purpouses.
This is no where near as polished as crazy bump, but it should be a nice free alternative or another tool for people wanting something different.
Anyone interested or did you already invest in crazy bump?
Here is a realtime blender scene that used Insane Bump:
Ok here is the installer, the install process is relatively complex since windows doesnt come with the dpendencies it needed on linux but its not hard. Run the installer and install all the dependencies that popup, the tricky bit is when this message comes up, follow whats in the image.
After the install the program should run, There are two stages to the texture creation process, one is loading and preprocessing(similar to what crazy bump does when its "thinking") then the second stage is realtime .
All the things for the first stage are in the first panel (with sliders A & B), the normal depth is self explainitory, while "Feature size" is a very critical variable. The feature size slider changes how Insane bump "sees" the bumps on the texture. Use larger feature sizes for more organic materials, while things like metal plates would use smaller feature sizes. After Adjusting these two variables and chossing any extra options like seamless textures click the Generate(button C), this will generate preview data for you to work on in realtime. The preview data is just downscaled version of your texture (this allows you to work on huge textures that exceed your card limits for offline applications).
Panel with the sliders labelled F are all realtime options that you can change, currently the viewer doesnt suppourt specularity but specular maps are still made. Only changes in these sliders will be seen in realtime, if you change sliders A & B you have to reclick Generate (button C).
Once you are done clicking save changes (button D) will reapply your filters to the high res original texture.
Panel E shows the controls, use the arrow keys to move around after pressing the Q key.
WARNING: this software recieved very little testing, no warranty etc...... The uninstaller will uninstall insanebump but not gimp and python that get installed.