I messed up my xorg somehow and now unity-3d doesn't work, but unity-2d seems OK. By doesn't work, I mean that when I boot into 3d, I only see a background image, no icons, panels, or anything else.
What are the most likely suspects for why this would be the case? I would like to get 3d back to the way it was before I messed up my xorg (or whatever I messed up), and am looking for configuration files I could reset, or packages I could reinstall.