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Real2rgb contains a colormap called thermal which is very similar to this one, in addition to many other alternatives (as Ged mentions).
A very useful colormap, which looks good both in color and in grayscale. I personally prefer this (in color) to the linear-gray alternatives in ID 23342, though the latter tool is perfect for its primary purpose of converting data to truecolor.
real2rgb (fex id: 23342) offers many new colormaps which map to linear grayscale intensity, and can also convert standard colormaps such as 'hot' to fulfil this criterion.