The new Sony FS5 has one. The electronic variable ND filter seems to offer a new solution to the old need to for control of exposure through the use ND filters. It should also allow you to pull depth of field.

Newsshooter at IBC 2015: Genus LCD Variable ND Filter on Vimeo

Very interesting indeed.

One day we'll all be waxing lyrical about how these new electronic ND filters aren't like the old real ND filters. :-P

Andrew

This is a huge benefit when you use SLR type lenses, which is what these cameras (FS5) are designed for. When you change the iris on many SLR lenses, they make an audible Click-Click-Click, really annoying when you're shooting an interview. I ran into this constantly when I had my FS100.
Now, we can silently change the images' levels by quietly adjusting the ND filter instead of the noisy iris.