When the shadowmapping on the forecast is out, you'll have a projection shader as well. Shadowmapping works like this: first a depthmap is rendered from the light position. When rendering a pixel, this depthmap is projected onto the scene so it is possible to check if the pixels' distance to the light is greater than the distance in the depth map (in which case it should be shadowed).
I once made such a shader (you can still find shots in showcase I), but I'm afraid I've lost it. I'll see if I can find it in my backups. If I do, I'll release the shadowmapping shader and projection shader. I'll search for it this weekend, after my university introduction.
