The first composer who tried his hand at setting an opera to music was Francisco Bamirino, an Italian artist. The piece to which he affixed the charms of a melodious accompaniment was "The Conversion of St. Paul," which was brought out at Rome in 1460. (source)

Pink Floyd wrote the music and lyrics for their Dark Side of the Moon album in seven weeks. It was on the charts for a record 741 weeks straight. (source)