greatel did great job implementing steep parallax mapping to BGE.
It picked my interest to look at other parallax techniques. I am also planning to implement relief mapping in near future..
But first.. I noticed that old parallax mapping has a flaw called texture swim - when viewed from sharp angles - textures starts to distort.. swim around surface. I kinda fixed that, not sure if i did right, but at least it works.
Also i messed around with UV and i came up with silhouette clipping - cheap technique, but effective.
and a blend.
Mouse/WASD - move/rotate camera
left mouse button - move light along with camera
edit: also done as part for Twilight22 project.