Australia: Locomotion - Kylie Minogue (shudders at the thought of hearing this song the day I was born, thankfully I probably didn't as my parents have a similiar taste in music to me).
America: I Just Cant Stop Loving You - Michael Jackson and Siedah Garrett (slightly better, though I don't think that's saying much in this case

)
UK: Never Gonna Give You Up - Rick Astley (okay, I wont comment on this , either to comment on the fac i've never heard of this song or artist).