My current personal media player of choice is a Microsoft Zune 80. One cool thing about the Zune is ability to "socialize" with others through wi-fi song and picture sharing, and its sharing of recently played songs though a social networking function on the web and in the Zune desktop application.
By enabling the social functions on my Zune player, I can share with the world what I have been listening to. Microsoft makes available some widgets that can then be embedded on other web sites, such as Facebook, MySpace, etc. Using the social features on the web site, I can discover new music by taking a look at (and a listen to) what other people with similar tastes are listening to.
Whenever I sync my Zune, my friends' most recently played and favorite songs are automatically pushed to my device. It's like having a bunch of DJs sending me their favorite tunes. I can't tell you how many new favorite artists I have now as a result of these Zune social relationships.
At the top right of this blog, you'll see a mini version of this widget. Here on this page you'll see a larger version that shows more detail about the artists and songs, and allows sampling of the tracks so you can hear the tunes, too. Look for the little play button when viewing an individual track.
What does this have to do with bike commuting? Nothing. I don't think I'd ever listen to my Zune while cycling. Certainly never while commuting in traffic. Bust music is fun, and music was meant to be shared.
And please... no comments like, "What's a Zune?" I get the joke, really. :)