Personalization permeates the World Wide Web today and search engine-, social networking-, and social media websites—like Google, Facebook, and YouTube—use algorithms to tailor search results and content to web users’ interest and past behavior on the Web. Author and Internet activist Eli Pariser has raised concerns about this trend and coined the term “the filter bubble” to describe the information silos he argues web users may find themselves in when browsing the Web. If Pariser’s theory holds true—that personalization algorithms presents self-similar content to web users based on the users’ past web behavior—what type of online world will users that consume far-right or far-left radical content find themselves in?