The Most Powerful Americans Over Age 80:
Slate has an interesting list. My thinking: Placing Justice Stevens at #1 reflects a common overestimation of the importance of the Supreme Court; though I'm no expert at all on business, my sense is that many of the top businesspeople on the list are easily much more powerful than Justice Stevens, if you define power as the ability to affect many people's lives in an important way. But I might be wrong; check out the list for yourselves.