There is (at least) one insanely expensive HDR-sensor. Mind you, not in a camera you can buy at your local photo shop (I have
to find the source for this one)
And, yes, you can (or let Photomatix do it for you) construct a HDR pic from a single RAW. So you'll have no prob with moving objects. But sometimes there are some strange side-effects. See here
The prob today is that the sensors may cover 12bit per color but jpeg does not chowmore than 8bits and many monitors don't do more than 8bit per color. So you already capture more HDR than can be normally displayed wihtout tone-mapping (or other) tricks.
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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