I have used rocks with an axe head to strike sparks, as an academic exercise. Took me about 30 minutes of blue language on an ideal day with char cloth - you don't get a lot of sparks from rock and steel, and they don't like to land where you want them too. I've also used a bowdrill and board - that was faster - about 10 minutes of fiddling and huffing, but I had pre-carved the board, and conditions were also ideal.

I think such things are a useful exercise and everyone should do them at least once. Nothing will teach you the value of a bic lighter more effectively