The power to control electrons. The possibilities:
-Shooting freakin lightning
-Flying, but making the ground charged and your shoes charged oppositely
-Telekinesis, making something else charged and make your hand charged opposite
-Several other related things, such as walking upside down on a magnetic ceiling
-Being a railgun. All you need is a quarter for ammunition.
-Making a chainsaw with ironsand. Just create a magnetic field in the shape of a blade, and magnetize the ironsand to it. It will vibrate so fast it cuts through trees :D