FreePCB is a free, open-source printed circuit board layout editor for Microsoft Windows, released under the GNU General Public License. It was designed to be easy to learn and easy to use, yet capable of professional-quality work. It does not have an autorouter (yet). Some of its features are:

1 to 8 copper layers
Board size up to 60 inches by 60 inches
Uses English or metric units (i.e. mils or mm) for most functions.
Footprint libraries courtesy of Ivex Design International Inc.
Copper fill areas
Footprint Wizard and Footprint Editor for creating or modifying footprints
Imports and exports PADS-PCB netlists
Exports extended Gerber files (RS274X) and Excellon drill files
Design rule checker
Autosave