Traditional removable batteries of the AA and AAA variety might be going the way of the dodo: Modern gadgetry that used to rely on them now use internal, rechargeable batteries. But there are still a good few items out there that need those defiantly old-school juice cylinders, like keyboards, mice, and remote controls.
Microsoft, in an odd bit of engineering, has created a system that removes the confusion of the positive and negative ends of batteries. Called Instaload, it lets you pop in batteries willy-nilly, without the extra second it takes to distinguish between + and -.
It works in such a simple way that I can't believe nobody else has thought to invent it (like, a decade ago, when it would have been a barn-burner): Both ends of the battery compartment contain both positive and negative terminals. The system relies on the different shape of the battery's ends: The pointy positive end touches a small, concave bit of the terminal, indicating a positive flow, and the flat negative end does not, indicating a negative flow.
Microsoft says it's offering "fair and reasonable license terms" for other companies to use the design, although considering it's mostly cheap items that still use those types of batteries, it may not take off. But you can expect to see it in Microsoft's well-regarded line of computer accessories, like keyboards and mice, in which it'll be a curious but nice little feature.