"Black and White" (1995)
In Bill Flanagan’s book U2 at the End of the World, Flanagan is present for some of the recording sessions for the Passengers Original Soundtracks album.
“Black and White” is mentioned in the book:
Some of the improvs get silly—on one experiment Edge, Adam and Bono play a dark, F sharp minor pattern a little like the Velvet Underground’s “Ocean” while Eno has Larry play a happy Japanese jingle on the keyboard in C major. Eno calls the result “Black and White” —because three of the band are playing all black key notes and Larry’s playing all white keys. It’s a clever notion, but it still sounds terrible.