The music of ABBA has long been a guilty pleasure for me. They burst on the scene when I was 2. (Actually, I was in high school.) I was "too cool" to openly admit I liked their music. They made catchy, hook laden pop songs, with great harmonies. The girls in the group looked great, too! The formula worked very well! Some of ABBA's records outsold the legendary Beatles. The first song I ever played on the radio was "Knowing Me, Knowing You." Anytime I fill in for CJ on the "Polyester Power Hour, " I play "Dancing Queen," because I know how much he hates it. The hugely successful musical & movie "Mamma Mia" are a testament to the group's lasting appeal. This Monday (April 7th) was the 40th anniversary of ABBA's breakthrough hit, "Waterloo." Watch the video & check out the costumes!...