Plastic Tunes is a “now-playing” plugin that allows your blog to display informations about the music you play in your media player, and most importantly, to insert them into your database. Artists, titles, albums and pretty much any information included in your digital music files goes into your database for real-time or later use, ready to be displayed on your sidebar, on a dedicated page or wherever you want. 
The concept of this plugin, and quite a few lines of code were originally taken from version 0.1 of the <a href="http://www.thesmithsplace.com/mutunes" rel="nofollow ugc">muTunes</a> plugin, made by Ken Smith — although Plastic Tunes grew a lot since then.

Plastic Tunes

A Multi-User "Now Playing" plugin that accepts input from iTunes, WinAmp, and many more. Saves your information to your DB and will accomodate multiple users. Widget compatible and highly customizable.

eprieto

This plugin get the info of your account in Grooveshark, and adds it to the sidebar of your blog for share it with your audience.

Wp-Grooveshark

This plugin adds info of your Grooveshark to your widgetizable sidebar.

Plastic Tunes vs Wp-Grooveshark