The first item on his list was a todo list. It's interesting because I once had (what I thought at least) was this killer idea for a personal task management app.

I was psyched about it until I went and pitched it to a friend of mine and he was like "It's a todo list. That is the equivalent of 'Hello World!' for product ideas. Don't do it."

Looking back, he was so right. I think every programmer I know has come up with an idea for a new spin on the todo list at some point.