Vocal Auto Tuner

[happyhappy]

Hey guys, I was wondering if anyone has ever used a Auto Tuner or knows about them. I was wondering what exactly they are... if its a software program where you load it up and speak through the mic and it adds the effect in real time.. or if its a peice of hardware. I was recently thinking about singing and I thought it would add a cool effect, its only for personal use. I heard T-Pain uses one on some of his songs.. like Buy you a drink. Id really like to buy this software or hardware whichever it is so if you guys know anything about them help me out!

 

[happyhappy]

I kinda like the fact that they sound unatural, what type of programs can do it on the fly just with you talking into the mic? Do you know the name of one I could purchase?