We all know that after an unfortunate experience with a bomb that literally had his name on it, Tony Stark needed a way to keep the unfortunately acquired shrapnel from getting to his heart, so he invented himself a handy little arc reactor that powered an electromagnet that kept it at bay.
But... why an electro magnet?
It make sense that he needed the reactor to power the suit he used to escape, so using it to power an electromag was a good cover story...
But it seems like a normal magnet would have been sufficient to keep him alive after he got to safety.
Is there some reason a normal magnet wouldn't have worked? This would have certainly have helped when he was dealing with palladium poisoning in Iron Man 2.