aasink aalib (http://aa-project.sourceforge.net/aalib/)
xmms libxmms (http://www.xmms.org)
decdvd ac3dec,mpeg2dec (http://linuxvideo.org/mpeg2dec/,http://linuxvideo.org/ac3dec/)
+sidplay libsidplay (http://www.geocities.com/SiliconValley/Lakes/5147/sidplay/)
Plugins derived from GPL code are as follows:
synaesthesia synaesthesia (http://yoyo.cc.monash.edu.au/~pfh/synaesthesia.html)
gst1394 libraw1394 (http://linux1394.sourceforge.net)
flac libFLAC (http://flac.sourceforge.net)
RTP ortp (http://www.linphone.org/ortp/)
+Effectv effectv (http://effectv.sourceforge.net)
Plugins which use a BSD covered library are as follows:
vorbisenc libogg/libvorbis (http://www.xiph.org/ogg/vorbis)