Most Peaceful Music you've Heard or Own

Arvo Pärt, "Alina", on ECM. May be a little subtle for traffic but it's great at bedtime.

Almost any of the a capella Renaissance masses. Performers include the Tallis Scholars on Gimell, the Clerks' Group on ACV, the Huelgas Ensemble on Sony and Harmonia Mundi. Composers include Josquin Desprez, Ockeghem, Pipelare, Byrd, Lobo and lots more. If these are all new to you, try the Ockeghem Requiem (Clerks, ACV) or the Richafort Requiem for Josquin (Huelgas, Harmonia Mundi).

Le Pas du Chat Noir by the Anouar Brahem Trio.

Hey, Kind of Blue, but you already thought of that one.

Philip Glass : Aguas da Amazonia
http://www.amazon.com/Philip-Glass-Aguas-da-Amazonia/dp/B000HWY5ZW/ref=sr_1_63?ie=UTF8&s=music&qid=1247747940&sr=1-63

Tord Gustavsen Trio : Being There
http://www.amazon.com/Being-There-Tord-Gustavsen-Trio/dp/B000NVL4EM/ref=sr_1_4?ie=UTF8&s=music&qid=1247748212&sr=1-4

Music of Ernesto Nazareth

The three piece Bob James stuff works for me. No vocals.

Pat Metheny and Charlie Haden "Missouri Sky," Antonio Forcione and Charlie Haden "Heartplay," Richard Stoltzman "Begin Sweet World" and "Dreams," Enrico Pieranunzi "Ballads," Charlie Haden and Kenny Barron "Nightfall," Charlie Haden and Gonzalo Rubacalba "Nocturne" and "Land of the Sun," Van Morrison "Poetic Champions Compose."