I've done:

- Accounting system used for real life taxation in my self-employment: https://gist.github.com/lf94/fcdf41776e14fcc289bac652ea8cb4f...

- Software shader rasterizer for image generation: https://gist.github.com/lf94/f74c927e59b4010d9de001fa2ba8791...

- PS4 controller macro system via an RP2040 & ZeptoForth: https://youtu.be/exayMSQfyqk, https://gist.github.com/lf94/2d64917728594516dee6caf7667d2e4...

- Iambic paddle tap interpreter for morse code practice (once again running RP2040 & ZeptoForth): https://gist.github.com/lf94/95516fa39c3339b685e0fde10f17c97...

- Fixed-point number library to run computations on pretty much any CPU in existence: https://gist.github.com/lf94/ca622ebac14d48915ea976f665f832c...

- 1-bit music synthesis experiments to learn how to make music with a beeper (useful in products, such as Tile): https://www.youtube.com/watch?v=IjTihhFG03o, https://www.youtube.com/watch?v=_6f8PURcPEE

And that's all in my rare spare time.

Forth really shines in microcontroller or esoteric computation machines, but further more, people don't realize their C compilers are billions of dollars of development, and they'd never be able to do it in the first place. A Forth on the other hand can be developed in a month (I'm being honest-to-god realistic here. A lot of people would say "a weekend", but let's be real, anything useful will be more than a weekend. I'm trying to convince you this isn't bullshit :)).

If you have any more questions let me know. I was bit by Forth about 2 years ago but had read about it long ago when I was like 16 and passed it off as too hard. It's the same shit as when FP took off: it's a different mental model, so it will take time to morph your mind.

Edit: read the larger comment below, and they are totally correct:

> most Forth tutorials today are written by people who don't really know Forth

One day I might write a small Forth novella teaching how to actually think about Forth programs. In these 2 years I've had to just practice and write programs to see common patterns or idioms - kind of exactly like when I was learning Haskell years ago.

This is pretty impressive!

I don't think it takes billions of dollars in development to write a C compiler, but it does seem like everyone's first C compiler does take at least a year, so US$100k is a good ballpark. I agree that Forth is about an order of magnitude easier. You probably shouldn't consider https://github.com/kragen/stoneknifeforth to actually be a Forth (it's not interactive and doesn't have immediate words) but it did compile itself into a working ELF executable and it did take me almost exactly a month to write (October 02008, specifically). I could probably write a real Forth now in a month.

I would be very excited to read your small Forth novella. Or your small Haskell novella.