I have checked out a lot of good resources and examples of responsive designs.
But I felt, they all are tweaking the layout according to the screen sizes of client browsers.
Try opening a responsive web page in a wide screen and keep on changing the browser widths.
I feel, how they adjust to the screen size won't probably save the bandwidth on a mobile device.
Rather, we might have detected a mobile device and really send a small-screen based template with minimal contents, and low quality images, etc.
What would you say?