ZDir is a tiny DOS directory lister that I started years ago when I was in high school. Compared to the dozens of other directory listers of the day, it was the best-- ZDir automatically determined how many columns to display, it could display a full tree, the colors were completely configurable, it worked in any text mode, no matter how non-standard, and it was lightning fast (written in assembly language). ZDir was available as shareware, and was quite popular, though it's not very useful any more because it does not support long filenames.
The last release was in 1994. Please don't send in any registrations any more!