www.Deathflag.com (http://www.deathflag.com) has a radio button on the index page.
Works perfect in IE, however there could be bugs for firefox and you may need the IE Tab plugin
http://www.phpbb3bbcodes.com/viewtopic.php?f=39&t=2566 (http://www.phpbb3bbcodes.com/viewtopic.php?f=39&t=2566)
worth having a look TiU could have a radio button on the index pointing to a shoutcast stream .pls or a .asx stream
an older radio mod
http://www.phpbb3bbcodes.com/viewtopic.php?t=1273 (http://www.phpbb3bbcodes.com/viewtopic.php?t=1273)