Welcome to the "80 Over 80," Slate's first-ever list of America's silver lions: fourscore elder statesmen, business leaders, and cultural icons who have remained influential into their ninth decade and beyond. We've ranked these still-twinkling stars according to their power and importance, with extra credit given for energetic achievements post-80 and for being really, really, really old. (We're looking at you, Studs Terkel.)

There's also a list of five "79ers to watch" over the next year—if these upstarts keep at it, they'll be a lock for next year's list. Finally, a selection of five seniors who "just missed"; each has in recent months taken his rightful place on a much bigger list.

Top "80 Over 80" honors this year go to John Paul Stevens, the oldest member of the U.S. Supreme Court and author of the majority opinions in Hamdan v. Rumsfeld and Rasul v. Bush. Truly a geezer among geezers, Stevens has demonstrated that he's still pounding the gavel with as much enthusiasm as a justice 10 or 15 years his junior. He may not be worth $18 billion like Kirk Kerkorian or have won a Nobel Prize or even a Pulitzer. But if the venerable justice were to die of natural causes tomorrow, every last American might feel the effects.

Congratulations, John, and hang tough.

Interactive feature designed and created by Holly Allen, Natalie Matthews, and Matt Dodson. Click  here  for complete photo credits.