Yellow.

A bright, cheerful colour. The colour of my school "house" for the past 11 years. Associated with victory, vibrancy, passion and activity in my mind.
A diseased, jaundiced colour. The colour of white food gone bad, aged paper, wasting skin, bile and rotting, infested things.
A sunny, positive colour. The colour of daffodils, sunflowers, a bright summer's day, fireworks and happy, lovely light.
A sinister, overbearing colour. The colour of forced smiles, psychedelic maniacs, and yellow teeth locked in grins.