Haven't really done this much before, so it was an interesting experiment. Unfortunately, I tend to overexpose a lot in-camera (like when I forget to change from M to Av, or i'm on Tv at slow-shutter and go outside into the sun with an f/1.4 lens wide open (i'm looking at you, Samyang 35).
So I've played around with a few photos, this first i call "Polar Bear in a Snowstorm":


Silliness aside, this Penguin was already a bit over-exposed in camera, was through glass using a CPL indoors, EF 50/1.8 @ 1.8, 1/60s iso3200, so already not the best shot. Just did some simple curves on it, then a 10-pixel blur to de-noise and cropped out an ugly corner:


But the last is my entry, same as the last assignment this was taken just outside of where i'm now working for a different project. I though it was a bit appropriate because the piece of machinery was named 'Light' (I presume after Colonel William Light, other bit of machinery were named after other famous SA historical figures).
It was already at +2 as part of bracketed shots for HDR, then I did some fanciness on it: selected all but the 'LIGHT' text, the orange block and tackles and the red warning light, blurred the rest at 4-pixel radius, then did a first round of curves-adjustment. Then on the whole photo did another 4-pixel blur to get rid of the ugly border around the first selection, and a final curves-adjustment. Hardest thing was to actually get the curves high enough to fit in the 'high key' theme but still retain some information on what the hell it actually was (so I hope it's 'high' enough).