I managed to fix alot of the distance problem by stepping the the ray position distance from the camera, that gets the really far areas without much problem, its just those horrible bits where the rays just hover over the peaks where eventually it wont even draw a pixel there. the amount of steps and amount of final binary honing is hardcoded into the exe unfortunately so you guys wont be able to play with that... except for resolution. if you want, theres a function in the shader called gete, (which is called by get_distance) you could try taking out a few of the noise octaves and see if it runs a little smoother, as the shader compiles at runtime.
all the raycasting happens in ps_land, anyway. only prob is i coded it a little dodgy and gete has a sister function getge which should also be modified.
Necrolis, yeh sorry I forgot to mention its cursor keys and right click is mouse look.
660Ti sounds like a beast of a card.
If you guys wanted to keep the demo to try out on a future video card, theres no better pixel shader benchmark than distance field raytracing, IMO.
My twin gtx690 is about three times the speed of my gtx480 at it... its a good test.