I've been seeing these little notepads everywhere and I wanted to try them for myself. This obsession was at it's worst at about the time that I realized that the office I work at throws away a ridiculous amount of cardboard file boxes and large envelopes. End result: cute little notepads made from recycled office materials and decorated with paint, whiteout, and permanent marker.
Just cut out a 3" x 1.5" strip from the thin cardboard. Fold in at just under half way and fold the other end over. Cut out a little stack of 1" x 1" papers from scraps. Slip the paper stack into the small fold side and staple. You can decorate them with paints or markers.