Viral marketing videos are a powerful force for pulling in tens of millions of views on the web. They are also the most commonly shared things on social networks like Facebook and Twitter. There are entire websites devoted to showcasing the funniest video clip of the moment, such as FunnyOrDie.com.

This site is well known for its hilarious and self-deprecating celebrity cameos from the likes of Will Ferrell (one of the site's original creators), Zach Galifianakis, Lindsay Lohan and Natalie Portman. The site has a staff of about 20 writers and filmmakers that create up to 30 original videos a month. It also allows users to upload homemade videos, and is a frequent stop for celebrities who want to create a viral buzz ahead of a new project. All of this translates into real currency for the studios in terms of more TV and movies sold.