Duke Ellington and his orchestra recorded a famous song Mood Indigo about the deep blue color,indigo.

VOA: special.2009.11.15

Half our coral reefs are dead or dying. We've lost 90 percent of deep blue water,big game fish: the halibut,the tuna and the marlin that we all loved to eat.

VOA: standard.2010.08.04

Beyond, purple-shaded mountains rise from the deep blue mist like ships floating on water.

BBC: A tranquil slice of Tanzania

Austin, essentially, reaps the benefits of being a deep blue, Democratic island in a red-state sea.

FORBES: Austin's Secrets For Economic Success

Deep Blue was programmed to "see" the chessboard and to counter with the best move.

FORBES: The Smartest Of Them All