Here's something different. The-Dream just released "Tron," which will appear on his upcoming IV Play (out May 4th), and over warped synths he raps (yes, raps) in a pitched-down voice at a vague swath of his R&B contemporaries. Through all the vocal effects and anger (also the fact that he is rapping), he's barely recognizable.
Stream: The-Dream, "Tron"