Use sed to style sicp w/ the same indetation has the linux kernel. Everyone will think you are reading code, when you are reading sicp.
My preferred method is to dither the xterm bg with something I am looking at, and the fg is all code I am supposed to be working on. I just use my glasses, and place the filter on them to read the dithered bg. Transparency is also an option, but recognizable by nearby colleagues.