A simple 2x2 grid with one cell filled in so that the opposite corner can be filled in to complete a binary sudoku game. This could be a starter sudoku, so that you have a success to build on. Or have it as a party favor at management seminars.

Binary Sudoku is pointless, but ternary Soduko might work. Cells A1, A2, and B1 are one part, cells A3, B2, and C1 would be another part, and cells B3, C2, and C3 would be the last part. I've spelled Sudoko three different ways.

Quaternary Sudoku is more aesthetically appealing than six-symbol Sudoku (using 2x3 sub-blocks) but even that isn't very interesting. There are 288 different arrangements of numbers on a 4x4 Sudoku board, and I would expect that they can all be produced from each other via isomorphic transformations (e.g. reflection, transposition, remapping, swapping rows and columns, etc.)

For an electronics class, I built a binary sudoku game, where each square in the grid contained two colored lights to represent the numbers 1-4. It was hard to play.