pcb is a printed circuit board layout tool.  It includes connectivity driven
layout (rat lines), a layout versus netlist check, design rule checker as well
as industry standard RS274-X (Gerber) photoplot export.  Other features include
  - PNG/JPEG/EPS output for documentation
  - Bill of materials output
  - X-Y pick and place output
  - Two different autorouters
  - Growing footprint library