UVI Falcon - Sampler/synth hybrid instrument
Voicemod - What are the voice changers? How do these work? Are these illegal? What is a soundboard? Find all the answers here. Voicemod - The Best FREE Voice Changer
Pianoteq - Pianoteq is a virtual piano that runs on your computer.
Clownfish Voice Changer - Clownfish Voice Changer is multiple voice changing software for various chatting and gaming platforms.
LinuxSampler - LinuxSampler - free, open source pure software audio sampler with professional grade features.
GSnap - With GSnap you can get an auto-tune effect.