Using a Mining Reagent (this is made in the hellfire Forge) (Reagent) and an iron pickaxe (Catalyst) will create a Fast Mining array. When walking into it you will take about half a heart of damage but you will be given a Haste 3 potion effect. This has a 10 block (on both axis) radius:
The Mining Reagent recipe and the Fast Miner Array
Every 30 seconds this array will damage you again (half a heart) and refresh the potion effect. This also works for combat!