For whatever reason spheres in an image seem to appeal to people in general a lot more than a collection of big triangles, no matter how well shaded / textured and lit they are... So to get a bit of "ooooo" and "aaaaah" factor going I decided to add spheres to cudart over the weekend.
Of course, as well as looking better than a triangle, computationally they are much quicker to compute. So even with 111 objects in the scene and 2 levels of reflection it is still possible to get close to 20fps at 800x800. I have just finished an interactive demo version which I will make available for download here as soon as I've sorted out the license agreement. In the meantime here are some screenshots.