And now to the U.S. where celebrities are signing off their social media accounts - at least for a little while. Alicia Keys is spearheading a new campaign called Digital Life Sacrifice on behalf of her charity, "Keep a Child Alive."

With it, stars like Lady Gaga - who has more than 7 million Twitter followers alone - will stop using their various accounts on World AIDS Day on Wednesday, until Keys' charity raises at least one million dollars for children with AIDS.

Other A-listers to go dark include Justin Timberlake, Jennifer Hudson and Katie Holmes. Fans are encouraged to "buy back to life" their favorite stars - some of whom, like Kim Kardashian, have been photographed in coffins, their online personas dead until further notice.