A single line stamp, such as this XStamper N05, can be anything you want it to be. Use it to "veto" a vote, stamp something with "caution" or "danger" or use it for "classified" documents. Combine it with the perfect font style to send your single word message with double the importance than standard block lettering ever could.
This stamper is 1/8"x 2 3/8". The stamped surface does not have to be any bigger than your pinky finger, but it should not be too small either. Use this for logos and special dates (stamping wedding date in invitations) too.