Smithers: Well, Sir, you've certainly vanquished all your enemies:

Smithers: Well, Sir, you've certainly vanquished all your enemies: the
Elementary School, the local tavern, the old age home...you
must be very proud.
Burns: [stuffing money into his wallet] No, not while my greatest
nemesis still provides our customers with free light, heat and
energy. I call this enemy...the sun.
[throws a switch; a control panel appears at his desk]
[another button slides the floor off a model of Springfield]
Since the beginning of time man has yearned to destroy the
sun. I will do the next best thing...block it out!
[another button raises a shield over the model town]
Smithers: Good God!
-- Burns' dastardly plan revealed,
"Who Shot Mr. Burns? Part One"