For the sake of those who don't know, an "octogenarian" is someone who is in their 80's. In Slate.com's annual "80 over 80" ranking, our beloved Prophet, Thomas S. Monson was ranked as the most powerful octogenarian in America, which also included those in their 90's and beyond. This is not surprising seeing as how he leads a Church with millions of faithful followers.
Other notables on this list, although I'm not sure why they are considered "powerful," were Joe Paterno at #25, Jack Kevorkian at #38, Betty White at #40, and Stan Lee at #45. Interestingly, Billy Graham was ranked at #78. Also, this may be one of the only times a Prophet of God would be associated with the likes of an adult magazine peddler - Hugh Hefner at #19.