Related Clues:

• Without value
• Otiose
• Deranged
• Screwy
• Extremely enthusiastic
• Idiotic
• Demented
• Ineffectual
• Touched in the head
• Of no value
• Like a fifth wheel
• A waste of time
• Serving no purpose
• Environmental slogan, or a hint to this puzzle's theme answers
• Half-baked, as ideas