Related Clues:

• Diner check
• Subject of this puzzle's theme
• Diet soft drink
• Cash alternative
• Once-popular diet soft drink, or part of the can
• File-folder feature
• Debt note
• Loan letters
• It may be used to track shots
• Payback without the payback
• Chit letters
• Soda can ring
• Key above Caps Lock
• Drink in a pink can
• Note from someone shy?