Related Clues:

• Bit of horse sense?
• Waiter's bonus
• Helpful hint
• Good thing that comes to those who wait?
• Money on the table, maybe
• Part of an iceberg
• Detective's lead
• Iceberg part
• 15%-20%, usually
• Help line?
• Part of a pointer
• It's left on the table
• Subject of an anonymous call, maybe
• Service bonus
• Bit of help