Check out these plans from WOODstore.net, if you are looking to build your own humidor.
This classic project features a Spanish-cedar lining for slowing moisture transfer and maintaining a humidity level ideal for cigar storage. The wood not only tolerates high humidity, it provides a pleasant aroma.
Not a cigar aficionado? Simply forgo the lining and use the box to store jewelry or other keepsakes. The box holds up to three ventilated trays. Choose between two styles of patterned top. Included with these plans are a detailed article on Installing Quadrant Hinges.