Banshee is a good MP3 player, only works on Linux distributions and MacOSX though - http://banshee-project.org/

TiMidity for Midi editing - http://timidity.sourceforge.net/

Notepad++ code/text editor - http://notepad-plus.sourceforge.net/uk/site.htm

TextPad is another text editor - http://www.textpad.com/