gEDA-user: board-flipping plugin

[DJ Delorie]

I needed this to panelize one of my boards.  What it does is up-down
flip EVERYTHING on a board, without changing any layers.  The result
is a board that is a physical mirror-image of the original.  While
this doesn't produce a usable physical board, it does let you print
both mirrored and unmirrored panels on the same page by pasting a
flipped board into a panel with an unflipped board.

If you then swap the copper layers, you should end up with a
physically identical board that's flipped in PCB.

http://www.delorie.com/pcb/boardflip.c