XULPlayer is an Open Source multimedia player based on Mozilla Xul and MPlayer that supports a lot of audio and video.
One of the most important details of XULPlayer is the dual play, that allows you to visualize two videos simultaneously, although it doesn't mix the audio but you can listen to only one.
During the video playing you'll be able to modify the settings, color or aspect ratio. XULPlayer also offers information about the codec, number of frames per second, resolution,...
Finally, XULPlayer allows you to capture video screenshots while it is being played and see the lyrics of a song, as long s surf the web thanks to its built-in browser.