Laser and CNC CAD tips

Useful Sites

Making Gears

http://woodgears.ca/gear_cutting/template.html

It's nice and easy to understand and perfect for making laser cut gears with a specific pitch and tooth count (e.g. cnc belts on eBay can be found in 5mm pitch which is great for homebrew CNC stuff)

Making Boxes

http://rahulbotics.com/personal-projects/boxmaker/