Now for something totally different…light switch covers.
You could easily make these for recptacle covers also. Using a 3/4″ thick piece of pine or 1/2″ thick piece, route out the back of the cover so that the actual switch plate can be recessed in behind. If you use the 3/4″ material you may have to get longer screws. I would not advise taking off the actual cover plate to just use these. I think it would make for a fire hazard.