The sound loop you are probably listening to right now (if your browser is able to automagically play MP3) is my modest creation of a short afro-cuban Rumba Guaguanco with the wonderful open source drum machine Hydrogen which is freely available from http://hydrogen-music.org.
The source file for the loop you are listening to is available for download right here: guaguanco.h2song.gz. I consider this file as a very modest addition to freely shared musical culture and therefore you can do whatever you please with it. To get a proper sound representation with Hydrogen you need to download and load the following drum kit: http://www.hydrogen-music.org/getfile.php?file=ErnysPercussion.h2drumkit
Unfortunately, Hydrogen currently does not support non-*NIX operating systems, so Windows users will still have to wait quite a bit for it to become available for them too. If you can't wait, just switch to MacOS X or Linux in the meantime.