physmouse

Windows lines displays up in pixels. When monitors differ in size or sit at different heights, the pointer can jump vertically or fail to cross at certain positions. physmouse lets you arrange screens by their real desk layout and maps the cursor between them by physical distance. It includes a visual layout editor, automatic per-monitor sizing, and a full-screen lock enabled by default to help keep the pointer on the gaming display in borderless fullscreen.

I originally used LittleBigMouse, but in my setup the cursor could slip onto another monitor during borderless fullscreen gaming. physmouse is a small, single-executable Windows utility with a modern settings window and a per-user installer. Normal use does not require administrator rights. It is free and open source under the MIT license.

Pros: Physical-size layout editor; fullscreen cursor lock; modern settings interface; small single-executable app; per-user installer.