Related Clues:

• Preparation that needs a cracker?
• Set of principles
• Word with bar or area
• Nil
• Secret signal
• Diddly-squat
• Bagel
• It's really nothing
• Less than a few
• Not a whit
• Nary a one
• Write, as a secret message
• It's nothing, really
• The 'C' in U.P.C.
• A spy may crack it