Slaw,
One more from Daryl Hall (& Oates) - "Every Time You Go Away". Even though Paul Young had the hit with that song, Hall & Oates' original version is IMO every bit as compelling. Now, none of these Hall & Oates tunes may actually be the "best pop song ever", but Hall & Oates gave us some truly great pop music. Plus, if I could sing like one person, Daryl Hall would be on my short list. That guy can sing anything.