Related Clues:
- Noggin nugget
- Brainstormer's output
- Bit of creativity
- Start of a theory
- Playfulness
- Brainstormer's pursuit
- Comic-strip light bulb
- Brain matter?
- Invention's beginning
- It may pop into your head
- Entrepreneur's starting point
- New thought
- Reason to shout "Eureka!"
- "Hey, what's the big ___?"
- Invention inspiration