Hand-drawn grayscale fonts have been an interesting idea for some time, but have never really caught on. They certainly take a lot more skill and patience to do well than ordinary bitmap fonts.
That said, I think they can fill an interesting niche in the 100-130 dpi resolution range, which is of course where the vast majority of all users live today. At lower resolutions (in particular 72dpi, which was standard for a long time), the grayscaling is quite visible, which can be distracting. At much higher resolutions (say, 200dpi), hand-tuning is a waste of time because outline fonts can deliver somewhere around 95% of the optimal contrast levels even without sophisticated hinting techniques.
And, indeed, grayscale bitmap fonts are starting to come into existence. Check out this thread on typophiles about Firefox text rendering, and this one about monospaced fonts for programming. Also see the bitmap critique forum for some striking examples of grayscale (and monochrome bitmap) work.
Can we use grayscale bitmap fonts on our free software platforms? In theory, we should be able to, because Freetype2 supports the grayscale bdf format, as I was able to verify with the ftview demo program and a hacked-up font. However, if I put that bdf file in /usr/local/share/fonts (with a corresponding <dir> tag in .fonts.conf), then "xterm -fa Graytest" bombs quickly with a floating point exception. I don't really feel like debugging that right now.
So, I want to know a few things. Is it possible, by hook or by crook, to get fontconfig-enabled apps to load grayscale bitmap fonts out of the box? If there are stupid bugs keeping that from happening, how do we get those fixed?
I sense there is something of a chicken-and-egg problem here. If there are no good grayscale bitmap fonts out there, then there isn't a strong motivation to build support into infrastructure and apps. Conversely, if it's nearly impossible to deliver grayscale fonts, why spend the time drawing them?
But it may well be the case that the energy barrier is not that high, and that with a little directed force, we can break through it. Does the community have the collective will to make this happen, or is this just yet another of my crazy ideas that nobody cares enough to do anything about?