We started our design calling the side of the board with the surface mount components as the "top". When we build the the flying arduino compatible, the frame of the helicopter mechanism will be mounted to the upper surface of the board, so the electronics will be facing down. As soon as we started talking about the mechanical design, we realized how confusing it was to have the electrical "top" of the board on the mechanical bottom.
So we selected the whole board and flipped it. Which made it painfully obvious that the text I had silk screened on the "bottom" (now top) was in mirror writing. Oops.
So now I have learned: Write, then flip, or flip the whole thing to get readable text on the far side of the board.