Food

so just stick over hob, leave to heat for a while, then whack something on it?

sweet, might try some butterfly'd chicken breasts tonight

Yeah definitely - Wait 'til it's smoking hot then sear with it, or you could sear and then throw it in the oven to finish. But really you can use cast iron pans for so so much, baking eggs, making pizza/bread, hitting people over the head... so many options!