Auto Tune!

From the Wikipedia entry on Kanye West's "808s & Heartbreak":

The album relies heavily on the voice audio processor technology of Auto-Tune. "We were working on the remixes for Lil Wayne's "Lollipop" and Young Jeezy's "Put On" and he fell in love with the Auto-Tune," Dean explained.[9] Towards this end, West enlisted T-Pain for coaching on how to properly utilize Auto-Tune.[11] West himself openly stated that he loves using Auto-Tune and is dismayed that the term has been commonly associated with being "wack." He considers the technology "the funnest thing to use" and compared the situation to when he was a child and thought the color pink was cool until someone told him "it was gay." He went on to state how the views of society can rob people of their confidence and self-esteem.[12] He later went on to state that he enjoyed the electronic feel produced by Auto-Tune and sought out to juxtapose the mechanical sounds with the traditional sounds of taiko drums and choir monks.[13] It was revealed that the occasional exaggerated vocal effects produced by Auto-Tune are meant to represent the effect of being heartbroken.[14]