What is the average color of the universe?
According to astronomers at Johns Hopkins University, it's beige. Note, they previously announced it was turquoise, but they identified a bug in their calculations, redid the numbers, and now it was determined the average color is beige. Kind of boring, yes, but kind of what you'd expect.

In short, they collected "detailed light measurements from more than 200,000 galaxies. They then constructed a "cosmic spectrum," which represents all the energy in the local universe emitted at different optical wavelengths of light" and averaged it. More details at link below.

NPR : The Color of the Universe Is...