For decades futurists have prophesied that all your home's gadgets will talk to one another. This year a host of players, from communications providers AT&T and Comcast to hardware makers Sony and Samsung to startups like Nest and Quirky, are launching Internet-powered products and services that could help fuel the long-awaited machine-to-machine movement. Consider the Dropcam Pro, a surveillance camera that began selling at Apple Stores on Oct. 22. Using a low-energy version of Bluetooth, the camera's radio chip could allow it to communicate with other Internet-enabled devices in your home. Dropcam is betting that in the future its product might serve as an Internet hub, allowing you to manage other devices from the same smartphone app that lets you remotely peer inside your home. Here are some other companies pursuing similar strategies: