GMusicR is a Chrome Extension that allows you to remotely control the Google Music Player. Communication works by relaying messages through WebSockets using a third server. It is open so everybody can run their own. The server is also open source, see here.
This software is not tested. Further, the only security measurement to prevent others to skip your songs is the use of a secret. Everybody using the same secret can control each other's music.
Install From Here
gmusicr by Jan Kolkmeier is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.