This is one of the most common and easiest ideas to do with old corks from wine bottles. Since corks are basically just taken out of tree trunks, no two pieces are alike. Their surfaces are unique. Therefore by turning them into stamps you also have a unique design without having to spend a single penny (okay, maybe just a few for your stamp pad and ink?). These are great for personalizing your invitations and letters.
Materials:
- Cork
- X-acto Knife
- Pencil/Pen
Steps:
Draw an outline of desired shape on the bottom of the cork.
Using the X-acto knife cut a line around the cork which is about 1/8-inch deep. Also trace the outline of the shape to get rid of the unwanted parts.
It’s that easy!
We think these are better than store-bought ones, don’t you think? 
Source: The Pink Doormat