OK, so at some point I was shown or otherwise just stumbled across a sudoku that had green dot indicators for when one finished a row, column, or box. For rows, the dots would appear on the side, and for columns the dots would appear on the bottom, if I'm remembering it correctly, but maybe on the top. Boxes had green dots appear in one of the outside corners (I forget which). Also, if I'm remembering this right, finished areas had all of the boxes highlighted in green.
Anyway, searches for this have turned up fairly dry (any search that includes "sudoku" (despite what else is included) returns a plethora of irrelevant results, and those that don't turn up results that one would expect from "green" or "green dot"), and I don't remember how I got to it. I liked the interface, though, especially since it helps one to keep track of something without having to just look at the sections of text. So, if you're reading this and know where I can find that, then post a link in the comments. Assistance with this matter will be appreciated.