alt Hacker NewsWith current LCD controllers but new drivers/firmware you could selectively refresh horizontal stripes of the screen at different rates if you wanted to.
I don't think you could divide vertically though.
Don't think anyone has done this yet. You could be the first.
I believe E-ink displays do this for faster updates for touch interactivity. Updatimg the whole display as the user writes on the touch screen would otherwise be too slow for Eink.