Epic Rap Battles of History is a Youtube sensation by Nice Peter and Epic lloyd. The whole concept is that the watchers can suggest two persons that they want to see in a rap battle. In the videos they have for example featured Justin Bieber, Gandalf, Adolf Hitler, Darth Vader, Stephen Hawking, Napoleon, Gengis Khan, Albert Einstein, Easter Bunny etc. Nice Peter and Epic Lloyd Ahlquist are usually acting the characters, yet they've had numerous guests like DeStorm and MC Mr Napkins.
You can see what they have done on their website http://www.epicrapbattlesofhistory.com/ Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.