Happily, it was an old traditional folk song I like very much, "Scarlett Ribbons," which Harry Belafonte had a successful and terrific recording off, so that was another reason I let it play.
Eventually, I stopped working and just listened, quite taken by the woman singing. I had no idea who she was, perhaps a gospel performer which Garrison Keillor often has on, I didn't know, but it was very evocative. So, I went over to the site to take a look.
To my amazement, it was...Renee Fleming!
Usually when I've heard opera singers perform popular songs, their vocal training is such that it's clear they're opera singers. With some, perhaps with most, it just doesn't translate. The very best though do occasionally pull it off wonderfully -- but even there, it's still usually pretty obvious they're opera singers. Thomas Hampson has some terrific CDs singing Broadway -- one particularly wonderful one performing Rodgers & Hammerstein -- and those kind of songs fit.
So, for one of the world's great sopranos (the first opera singer ever invited to sing the National Anthem before the Super Bowl, last year) to sing a tender folk song so gently and movingly was a revelation. But then that's the sort of thing Renee Fleming does.
I tried to embed the song here. There's even "embed" code on the PHC site for it, but it plays another selection. And I can't link to it directly. But if you want to hear Renee Fleming's performance of "Scarlet Ribbons," click here and then scroll down the list of selections on the right-hand side, and click on it there near the bottom.