"You ain't been blue; no, no, no.
You ain't been blue,
Till you've had that mood_indigo."
–Indigo (web color) (#4B0082)
"This pigment (web color #4B0082) represents
the way the color_indigo was always reproduced
in pigments, paints, or colored pencils in the 1950s."
For related mythology, see indigo.
See also a search for "Coltrane + telepathic."