Nikon D800/D4 users, especially those who use HDMI recorders to recording 422 8 bit, the use of flat profiles allow you the best dynamic range. This is especially important when color grading/correcting, as the colorist has much more control over the image than the baked in curves which "fix" a look onto the clip.
There are 2 profiles I've tried. I can't upload the image captures but it's easily testable on your own.
The first one is Tassin profiles. This profile is based on the neutral profile of the D800 but pulls dynamic range a bit wider. It was originally designed for the D7000 but it does do the same thing with the D800/D4. However it's not optimized for the D800. It does add more noise once you go past ISO400 so use with caution.
The other picture control profile is Hurtado's Similaar Flaat suite, which is based on the portrait profile and consists of 3 different profiles, Flaat_10/11/12. Each profile number denotes the amount of dynamic range stops, ie 10=10stops etc. Like other profiles, as dynamic range is extended by pushing the blacks, noise is introduced, especially for 8bit video. I tested this on a D4 and it works "similaarly" 
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Both profiles give a nice flat picture that allows more dynamic range than the camera profiles. However, there's no such thing as a free lunch. The noise does increase and significantly as you push ISO. Use it wisely.
