World leaders from around the globe gathered in Johannesburg, South Africa, for Nelson Mandela's memorial service today. President Barack Obama was pretty busy during the event, giving a speech, shaking Raul Castro's hand, and, uh... taking a selfie with United Kingdom Prime Minister David Cameron and Denmark's Prime Minister Helle Thorning-Schmidt. The selfie, which hasn't been spotted on Instagram or anywhere just yet (and probably won't be since world leaders probably have their own exclusive social network), has to rank as one of the most star-powered selfies ever taken. 

On a related note, Michelle Obama looks pissed—and Barry might have gotten an ear full later on that night.