I’m sure this exact thing has been done many times before, turning a font into just counters or outlines around the characters that aren’t enclosed. I got inspired to try this after seeing counterless fonts several times, something that may have been inspired in turn by an earlier attempt at what I’ve just done.
Several of the letters were pretty easy, where there were many curves forming an enclosed or nearly enclosed space. The G and the Q gave interesting results, for example.
The S and the rest of the “straight line” characters were more challenging. On these I just filled out the surrounding space by connecting up points visible from each other.

This was just for fun, the result is readable with a fair amount of effort, but the more I look at it, the more it grows on me.

How would you handle letters like L, I and J, or W/M, and are there some well-known examples using this? This probably falls under use of negative space, but there’s more going on than just that, I think.