Lots of the above, especially Smetana's "Moldau." The two that first came to mind were "When Your Lover Has Gone" (Einar Aaron Swan, 1931), as recorded by Carly Simon on her My Romance album. The other is Rodgers & Hart's "Where or When," as sung by a resonant-voiced woman I was mildly enamored with (grammar cops, I'm sorry).
-Joe Offer-