I keep claiming to be the lame duck when it comes to music on this blog, but I keep stumbling across all these great info-tainment music finds. Like this one:
Peppe Giorri plays Gran Vals para Guitarra composed by Francisco Tárrega Eixea (1852 - 1909).
Just past 15 seconds in, see if you recognize "the most listened to melody in the world." Over 800,000 people all over the world play it several times, even during movies, every day.
[source] - don't click until you've figured out where you know this tune from.