Plus 1 for Mazzy Star.
Songs I never tire of include
Joan of Arc, and Messages by OMD
Today by Smashing Pumpkins
my angel rocks back and forth by Four Tet
Dayvan Cowboy - the Boards of Canada
Dash and Blast part 1 - Yndi Halda
but especially works of Sigur Ros; Festival, Glosoli, Ara batur, Hafsol are just top notch - really beautiful works.