Dark Frame subtraction

[mikb]

To steal an idea from the astronomy crowd, what about being able to use "dark frame subtraction" to cut down on hot-pixel and fixed noise features in cameras to make them work a little better in low light settings?

The camera would only need to be profiled once, with lens covered/in dark, to gather a handful of frames, which then are averaged together to reduce the effect of random noise. Then this image can be subtracted off future captured images.