There are plenty of mind altering substances in our diet. I eagerly await the day we can culturally accept that alcohol is an archaic drug, and we can replace it with modern alternatives that don't destroy livers and families.

Modafinil could already be a modern alternative to coffee. It's definitely not perfect, but in some ways it's a lot better and it seems to be safe enough. It's far from perfect - for example I'm in the 10% who get headaches from it, so I prefer not to use it. But when a better alternative comes... I can't wait to replace caffeine.