OVox Vocal ReSynthesis.

OVox turns a voice into a synthesiser, using what you sing to control eight synth voices across two engines. Vocoding and talkbox effects are part of it, but so are chord generation, arpeggiation, tuning and pitch effects, which take it well past the usual vocoder territory. It also converts a voice to MIDI in real time and sends that MIDI to any other instrument, so a sung line can end up playing something else entirely.