Eagle V6 and CNC router
PCB-GCODE (alternative site) is a free program that let's you convert from EAGLE's .brd file to G-code file.

These are the steps to follow (from this site):


  
  Enter the electrical schematic in EAGLE.
  Layout the PCB artwork in EAGLE.
  Run the PCB-GCODE.ULP program (from within EAGLE layout) to
  generate the G-code text files needed by the CNC machine.
  Use a G-code editor/plotter/viewer to verify and optimize the G-code
  files.
  Setup the CNC machine and mill the PCB isolation outlines using the
  verified G-code file.