There's a game on the BBC website called "Cyber Assault." It's a Risk-like strategy game where you fight against the Cybermen on the parallel Earth seen in Doctor Who. You're supposed to target the regions where the Cybermen have bases first, because when you destroy all their bases the game is over and you win whether the enemy still has territory under control or not.
I decided to make an artistic statement by instead defeating the Cyberman territories, leaving the bases intact, and using the pretense of their ever-looming threat to conquer the world.
(It's actually my headcanon that this is what happens after The Age of Steel. It fits with what we're told about the Cyberman situation in Doomsday, with the Cybermen defeated but sealed up in their factories. Also, Mickey Smith for World Dictator.)