The rendering method is Ray Casting, but the effect is custom and doesn't have a name that I know of.
I'm shooting a ray out from every pixel in the viewport and doing hit detection on a grid of cubes. Then depending on the coordinates hit on a cube, I map those to 2D textures (wall, ceiling, floor) to determine the color of each pixel. I also darken the color the further it is from the player to give a sense of depth.
The grainy/static effect is actually a side effect of a performance improvement. Instead of calculating every pixel every frame, I only do some pixels per frame. This leaves a bit of an afterimage if you move the camera quickly, but I like the way it turned out. :)