I once heard from a person that they created a Tetris system for themselves.

They would have created a task and connected it to a specific piece. Then, always when they did it, they'd color it inside the Tetris gameboard/panel.

• You can basically use whatever shapes and colors, and different rotations
• You can come up with different-looking levels (not just rectangles - what about a circle or a hexagon?)
• Maybe a nice reward when one row is filled? Or when the whole field is filled?