My dad and I were watching Wall-E today and we got to the part where Eve gets stuck to the magnet and Dad asks “If there’s no one left on Earth, who’s controlling the magnet?”. Does anyone have ideas about that?
Good question… I myself have always figured that whoever was running it just forgot to turn it off before he left Earth. He was all “Deedledee just workin’ with my giant magnet… oh dang it! The Axiom leaves the planet in ten minutes! Later giant magnet!” 
I agree with OWP, it’s power was proably left on. Or probably it was off, and at some point, WALL-E switched it back on without knowing one day while he was cubing garbage.
Good call! I never even thought about that. I guess I always just assumed it was left on.
Perhaps it was robotically controlled, but the drying of the seas left it unable to perform properly?
HAHA! ROFL! I laughed so hard when you said that! That was hilarious! Especially the “Later, giant magnet” part! XD