This performance is from the soundtrack of the movie Moulin Rouge with Nichole Kidman and Ewan McGregor. I was hoping to find an actual performance. The song was originally from a 1948 movie called The Boy With Green Hair starring a very young Dean Stockwell. I saw this on TV many years ago. You had to use your imagination since the movie was shot in black and white. Here's Wikipedia's write up about the movie. The link to Battle Star Galactica is interesting.