I'm picking Peter Gabriel's "1980 Games Without Frontiers" - kind of for two reasons.
First off - great song. It's off his third album, Peter Gabriel. Fun fact - his first four albums were called Peter Gabriel.
Second - and more of a new fun fact: Kate Bush sings backing vocals on the track.
I always assumed it was Gabriel himself with just a manipulation of his voice. But now that I know it's Kate, I can't unhear it and have listened to the tune a half dozen times in as many days.