In case you have been living in a hole, the newest sensor out there is Microsoft's Kinect sensor. It is made for the Xbox 360, but all kinds of robotic hackers are using it for stuff that it is not designed for. According to Wikipedia, "it enables users to control and interact with the Xbox 360 without the need to touch a game controller, through a natural user interface using gestures, spoken commands, or presented objects and images." In short, it is a major breakthrough in sensor technology, and it is relatively cheap compared to similar sensors like Lidar.
I know a person out there who can help us all out by writing some code so that we can use this awesome sensor with Mindstorms stuff (hint hint)