Sounds pretty interesting, Willie, I never knew of such a thing. Can you tell me more about this!!? Is there anything online that demonstrates that?

Autotune is a good one, it lets you play the notes on a keyboard (in the software or a real one via midi)
you can look for vocoders.. there's a few who will add some interesting artifacts..

Sounds like Autotune to me, and perhaps some Vocoder use as well... and very creative editing.

Here's another example:

[[url=http://[/URL]="http://www.youtube…"]Symphony of Science - 'We Are All Connected' (ft. Sagan, Feynman, deGrasse Tyson & Bill Nye) - YouTube[/]="http://www.youtube…"]Symphony of Science - 'We Are All Connected' (ft. Sagan, Feynman, deGrasse Tyson & Bill Nye) - YouTube[/]

i really dig that Dead Giveaway thing .... that is one talented producer that took those clips and turned them into that song .... and that's a lot for me to say that because i usually hate this kind of stuff. wowzers.

I usually use ableton live for production and creative stuff and I like to take vocals and chop them in whole words or into syllables. Then you can manually pitch shift each clip or drop each word/syllable into a sampler and play your melody with it. Gets interesting if you set up a multi timbral sampler or or set different words/syllables to different velocity settings and play your heart away. Once you have a good melody go back through and fine tune each peice a little so it all remains cohesive and in key. If you really wanna go nuts play Tim exiles the mouth or sugar bytes turnado over it to rapidly put different modulating fx over the sampled melody