As mentioned, corners are especially easy to hit, because they have two infinite edges. There is, however, one point on the screen that is even easier to hit: the point below the cursor. You don’t have to move the mouse at all to hit it. Context menus make use of this.
If a menu pops up below the mouse cursor, it makes sense to arrange the individual menu entries around the mouse cursor to decrease the average distance to each entry. One way to achieve this is by using a radial context menu.
Many games use radial context menus. Here’s an example from the LucasArts title Full Throttle:
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