Related Clues:
- Start of an invention
- Brain waves
- Inventor's ''step one''
- Bright one from gray matter
- They're sometimes funny
- Inventor's start
- Light bulb's signification, in cartoons
- Light bulb, in comics
- Mental glimmer
- Object of thought
- Head piece?
- Creator's sine qua non
- Brainchild
- Theory
- Lightbulbs, in the comics