These power duos prove that whether they're tackling global crises or ruling the world, sometimes it takes two. Here's a look at some of the world's most powerful couples.
A treasure trove of rarities, oddities and tech "firsts" has been brought together -- including an experimental 17th century mechanical calculator, a 108-year-old telephone and an incredibly rare, headline-grabbing Apple 1 computer -- to be sold at auction Friday in Cologne, Germany.
