All kinds of vocal processors, vocoders etc etc
http://www.kvraudio.com/get.php?mode=results&st=adv&soft=e&type%5B%5D=68&type%5B%5D=58&f=0&fe=0&win=1&free=1&com=1&un=1&sf=0&receptor=&sort=1&rpp=15
I don't think Antares Autotune is what you're looking for, it's main purpose is to make dodgy singers sound like they're in tune...
http://www.kvraudio.com/get.php?mode=results&st=adv&soft=e&type%5B%5D=68&type%5B%5D=58&f=0&fe=0&win=1&free=1&com=1&un=1&sf=0&receptor=&sort=1&rpp=15
I don't think Antares Autotune is what you're looking for, it's main purpose is to make dodgy singers sound like they're in tune...