I watched a documentary on Netflix about Ulfberht swords last night, which was really cool. And, at the end of it I started thinking about smithing in Skyrim and ways Bethesda could have made it more "realistic" for lack of a better word.
For example, the formula for making a steel ingot should be iron and charcoal with clay and glass, to remove slag or impurities from the steel, not corundum. And, what I thought would be a really cool addition to the game was the fact that Viking smiths used bone instead of charcoal on occasion, to give their weapons the strength of whatever animal provided the bones. How cool would it be to incorporate an animal (or peson) you killed yourself into your weapon?