Almost every ABBA song makes me deliriously happy, but Waterloo may make me smile the widest of all!! Waterloo was ABBA's first worldwide hit and the winner of the 1974 Eurovision Song Contest. Of course, the title comes from the lyrics describing a girl surrendering to romance, like Napoleon surrendering at the Battle of Waterloo. Cute. Undeniably catchy, Waterloo hit the charts all over the world, topping the chart in the UK and reaching #6 here in the US. It has sold over 6 million copies and is one of the best selling singles of all time. In 2005 it was voted the best song in the 50 year history of the Eurovision Song Contest. Suck on that, whoever else has ever won. (I have no idea) Anyway, I dare you not to smile and dance around while listening to Waterloo, by ABBA, your Happy Monday Song!