Related Clues:

• Inventor's germ
• Theory's start
• Potential dilemma solver
• It's out of one's mind
• Block buster?
• "I've got an __!"
• They're out of your mind
• Light bulb, in the comics
• It may be big
• Genesis of a plan
• Think tank matter
• ---
• Inventor's brainchild
• Mental creation
• They may be funny or bright