Related Clues:

• ''I had no __!''
• Hunch, say
• A lightbulb can represent it
• Gray matter matter
• Budding plan
• Writer's block buster
• Potential solution
• It may be fixed or bright
• Cerebral spark
• Inventor's "lightbulb"
• Light bulb, symbolically
• The very beginning of an invention
• 'Hey, what's the big ___?'
• Mind flash
• Creative input