Android? Meet hardware. Google is having a serious talk with external hardware, in a variety of ways, and it's not just mouse and storage support that's coming to Honeycomb 3.1.
First off, Google is announcing a new "ADK" (Accessory Development Kit") for Android 3.1. Accessories (like an exercise bike, or a robot) can hook up to your Android device over USB and talk to an app on your phone or tablet -- or point you to a specific app on the Market if you aren't set up already. To kick things off, Google is shipping some development hardware based on a Arduino Mega2560 board paired with a Circuits@Home USB Host Shield. The ADK is completely open source, with no NDAs or fees for developers. You can learn more here.
That's all well and good for nerds, but Google is also doing some more consumer-facing stuff with its brand spanking new Android @ Home tech. It's basically home automation for Android, with light switches and thermostats and all that. But that's just the beginning. "Project Tungsten" is the music side of things, which brings AirPlay-style music controls to that fancy new music app for Android. Basically Z-Wave, Sonos, and Apple should consider themselves put on notice. Google communicates to devices over some new wireless protocol, which we hope to learn a lot more about in the coming months. Lighting Science will ship Android @ Home compatible lightbulbs by the end of the year.