My choice is ELO's "Hold On Tight". This song continues to blow my mind after all these years. What at first seems like a typical blues progression is much deeper when you take a closer listen. There's a verse melody reminiscent of Jerry Lee Lewis, stacked harmonies that sound like Paul and John, and if that weren't enough, Jeff Lynne even makes room for a verse in French! Then the closing "Chuck Berryesque" guitar solo tops it off! As if I needed another reason, it's more proof why I feel Jeff Lynne is a genius. A classic example of using your influences properly and mixing them together to create a classic pop song. What are some of your selections for "most complex pop song under 3 minutes"?