Idea from Microsoft Office 2007's fade-in floating formatting toolbar.
Inspired by DimScreen; I'd like it to be interactive and apply just to graphics, or more to graphics and less to text areas.
Blocks out or dims all non-text graphics. If you need to see it, move the cursor near or over it and it fades in. Useful mainly in a browser for blocking out or dimming all images by default, but why not the whole OS?
Fade distance curve.
Blocking transparency %.
Restore to % transparency.
Color is user selected or some system color.
Keep unblocked graphics visible permanently or n seconds after mouse no longer over or moving near.
Redisplay limit n times so you don't see them more than a few times while the cursor is passing over.
Modifier-click for permanent display on/off.
There's a program UnderCover that removes the UI controls. Modifying it to be interactive with cursor position would be a start.