Oliver: I added this project to the ?page=support.

I have finished a bmf2bdf converter:
Features
- Convert .bmf to .bdf
- Converts DOS codepage to Unicode (-u option)
- Convert monospaced proportional font back to none-monospaced font (-p)
- Optional glyph spacing with -x
- Optional baseline adjustment with -y
- Brightness threshold with -l for multicolor fonts
- Generated BDF can be modified with gbdfed and FontForge
URL: https://github.com/olikraus/u8g2/tree/master/tools/font/bmf2bdf
The converter is a single .c file without other dependencies. Windows exe is included in the above folder.

Let me add some generic notes from my tests with the bmf2bdf converter:
1) Some fonts are marked as monospaced, but are actually proportional fonts.
2) The baseline seems to be shifted for some fonts (ok, it depends on the definition of baseline). But the problem is: The above bdf converter can't fix this: If the uppercase A is not placed on the baseline, then this is also not the case for the generated BDF.

Again, thanks for the effort and improvements for the filter.

@Oliver, @Joe: Allright, I hear ya. Did some changes to address this, added inputs to filter the number of colors and characters in the font. Yeah, the number of characters is not exactly the same as filtering whether the font has a lower case letters, I hope it'll be good enough for now, though.
Btw. you can still sort the search result by the number of colors in the font, as well as the number of characters in it. Also, you can filter just the fonts with ?tag=incomplete-alphabet.

I think Oliver makes good points. I also think it'd be great to be able to filter by number of characters in the font. Say I put in 64, it should show only fonts with 64 characters or more. Right now there's no good way to find more complete fonts.

Thanks for all the effort here. Great work.
While looking around here and exploring all the nice fonts I also was thinking about some improvements:
1. Seeing the full charset requires two clicks. What about removing the full charset expander and just keep the "load" button?
2. A filter for single and multi color fonts would be great
3. A filter for fonts with and without lower case chars would be also nice.
Thanks again.

I've found three Font Collections by Exile and will be adding font converted from pictures in those collections.
Unless there's any note in the picture, there's no telling about the name of the font or its author, so I guess I will have to set some name and maybe later, upon knowing more, renaming each.

I'm working on a GUI font editor for the BMF format (versions 1.1 and 1.2). This will be free and open-source. I have a decent start on it, but I am always short on time, so I'm trying a bounty system (bountysource.com) to recruit some help.

If you think a graphical BMF font editor would be useful, please consider chipping in a few bucks to the first bounty task:
https://app.bountysource.com/issues/111282532-feature-add-glyph-selection-to-fontedit

Or, if you want to learn MiniScript and Mini Micro (these are easy and fun!), you could tackle the task yourself and collect the reward!

Right now we've got 3,081 proportional and 3,081 monospace fonts in store.

Wow! Such an amazing and helpful post this is. I really really love it. It's so good and so awesome. I am just amazed. I hope that you continue to do your work like this in the future also.

I added few fonts from another source that I had found on the Internet - Dwarf Fortress Wiki (I added the site to the ?page=support page). Some more fonts from there will come. To my wonder, I still keep finding these resources.