I used Mosaic Magic back in my high school journalism class to design a yearbook cover 20+ years ago! Turned out great - it won some kind of award iirc.
One really nice use case for dithering that I've found is for building graphics for 8-bit (Pico-8 and Picotron) games and toys.
I made a ruby script that can take a graphic and scale it to whatever size, then it uses a closest color match to substitute colors for the _very_ limited Pico* palette and applies dithering to make it look attractive. I like Stenberg the most, but have played with Atkinson and am still feeling around a bit.