Here's a project using one of my tiny arduino boards based on the concept of the capsense library (although I ended up writing my own code) that I did with a linear series of 8 capacitive sensors. They are made from 1"x.5" pieces of copper tape. I stuck them to graph paper so that I could align and space them precisely. I then added a strip and a series of pads across the top so that I could mount an SMD LED for each sensor, and added a backing and border to connect to ground. It works extremely well when I touch the pads directly, and it also works through a sheet of paper or plastic, though I have to press a little harder (so that more skin is pressed up against the pad).