Its possible to have your now playing in rhythmbox be part of your away message or buddy profile in linux. These instructions were written and tested in ubuntu linux, but probably work in other distros as well.
1) Install ‘pidgin-dev’ package via your package manager of choice. Run the following in a termina:
sudo apt-get install pidgin-dev
2) download and extract the latest release of the pidgin-rhythmbox plugin from here
3) open a terminal and use the cd command to browse the extracted folder. Then, in the terminal, run:
sudo make install
4) Restart pidgin and enable the plugin via tools > plugins (in pidgin). While your in there, mess with the settings as you want them.
5) add %rb to your away message, profile, or available status
6) pause and start again the song youre listening to in rhythmbox. This refreshes the %rb code