Amazing Bump/Displacement Demo...can we do this?
Zoom into the maps, close...
press "T" to change the maps...
FYI- the bricks are NOT geometry...its all maps.
you can view the texture, bump and normal map with the demo.

Here is the Demo:
http://www.bostream.nu/tunah/offsetmap.zip

Here is the Glut, unzip to demo if needed
http://www.xmission.com/~nate/glut/glut-3.7.6-bin.zip

Here is the Thread where I found it
http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/011292.html