FlyMuzic said:That Robo voice is A VOCODER mate.
the vocoder is an instrument that combines 2 signals, generaly ur voice as one of the signal and the other signal (carrier wave) would be a synth sound or infact a guitar or what ever you want.
software Vocoders are ok but the frequencies are just a little harder to harness.
I use the MicroKORG thats got a real sweet Vocoder on it and its only £300 which is about $500 not bad!