Was going to see if somebody would bring that up. While it's true downscalling and upscalling in nearest neighbor will achieve this (kind of, i'll explain), they are still pixels, therefore, if you to scale down artwork that is already 1x1 pixel, pixels will get lost because you can't half a pixel. And because they are still pixels, you can't skew, rotate, or transform them without degradation. Now, if they were all "vector pixels", you could do all that and more, and in real time without re-scalling bitmap data.
Either way, sounds like I have a new weekend project, haha.