Well, not the actual Paul Simon and Art Garfunkel. They could be Cylons. Or perhaps angels! Yes, melodious seraphim who hung out with the primordial godhead Bob Dylan who wrote "All Along The Watchtower" during the Big Bang or something. Note: three-year-old, Gaius Baltar-related spoilers. (Hat tip to Brian.)
[Via Saul Tigh's YouTube]