Related Clues:

• Light bulb, in a comic strip
• 'Aha!' elicitor
• Flash of sorts
• Whimsical idea
• Strip light bulb?
• "The very ____!" ("What nerve!")
• It's out of your mind
• Writer's block breakthrough
• Brain gain
• Think piece?
• Think of it
• Potential problem-solver
• It might be half-baked
• Group of troops
• Child of invention?