The $10 Echo
One of the more impressive things about the Echo is its far-field mic. I've used a lot of different voice recognition technologies, but Echo blows everything else away in terms of being able to speak in a normal voice from the other side of the room and have it still understand you. The actual intelligence behind the service may be lacking (or at least behind some of the competition), but for a general-purpose home application, the mic (in my opinion) is a significant part of Echo's reliability and success.