Constantines and Feist - Islands in the Stream - Made famous in 1983 as a duet by Kenny Rogers and Dolly Parton, Islands In The Stream was originally written by the Bee Gees. A favorite of Constantines and Feist, the song was recorded together in Toronto one chilly day in early February following a game of ice hockey and a round of hot chocolates.

Thanks to Jewelgurl for tipping me off about this.