Nah, I'm guessing it relies on X.
Was annoyed, hacked fbgrab to not blow up on Kindle's fb.
Thoroughly untested and mostly coded blind, but seems to work.
Crappy K4 binary, will post proper ones tomorrow if people confirm it works.
@twobob: I get negative images with ffmpeg (well, libav actually). Got the same with my fbgrab tweaks until & 0xff saved the day.
It's 7AM, and I have no idea what I just did, but yay.
.