4 redstone torches, 1 redstone block(4.0, in 3.0 just fire), 8 redstone dust, 12 iron bars
1 use, produces a bound rune block
When the bound rune block is created, you can right click with runic armor pieces and it will be enchanted up to 5 times to give you a half heart for each enhancement
Right click the rune with an item of runic armor, it will enchant the item and when the armor is worn you will have more hearts, up to a total of double the base health. In 3.0 the rune has to be recreated every single time.