Add this to your iTunes podcasts, and you will start getting daily updates from the del.icio.us popular list.
Why is this cool? Well, it is like having thousands of people vote on what internet mp3s are interesting or appealing. So far, I've noticed that the popular list tends to be dominated by funny or jarring covers (e.g. Nina Gordan's acoustic rendition of the NWA's Straight Outta Compton).
Like everything del.icio.us, there is a deeply self-referential aspect to your enjoyment -- the podcast is entertaining, as is contemplating why these mp3s are popular.