4ormulator Vocoder Extreme
   Commercial vocoder for Windows with free demo. Supports more than 500 filters, formant manipulation and LFO control.
   http://www.vocoder-plugins.com/index.html

AnalogX Vocoder
   Free multiband standalone vocoder for Windows.
   http://www.analogx.com/contents/download/audio/vocoder.htm

Cylonix
   18-band standalone vocoder for Windows.
   http://www.cim.mcgill.ca/~clark/cylonix.html

Native Instruments Vokator
   High-resolution commercial VST plugin and standalone application for Windows and Macintosh. Also has synthesizer functions utilizing fast fourier transformations (FFT).
   http://www.native-instruments.com/index.php?vokator_us

OrangeVocoder
   Realtime commercial VST plugin for Macintosh and Windows. Many examples and demo available for download.
   http://products.prosoniq.com/cgi-bin/register?service=showdetail&refno=31/

Settel Vocoder
   16-band standalone and LADSPA plugin for Linux.
   http://www.sirlab.de/linux/descr_vocoder.html

Zerius Vocoder
   Free simple standalone vocoder for Windows, Mac and BeOS.
   http://www.epiphyte.ca/code/vocoder.html