Ellen DeGeneres
While hosting the 2014 Oscars, DeGeneres temporarily shut down Twitter when posting this epic selfie — with Meryl Streep, Julia Roberts, Jennifer Lawrence, Bradley Cooper, Brad Pitt, Lupita Nyong'o and others — in an effort to garner the most re-tweets on the social media site. "If only Bradley's arm was longer. Best photo ever," the talk show host captioned the pic, which also featured an appearance by Nyong'o's brother.