15 Secrets Successful People Know About Time Management: The Productivity Habits of 7 Billionaires, 13 Olympic Athletes, 29 Straight-A Students, and 239 Entrepreneurs

by Kevin E. Kruse

A very powerful tactic is if you can’t take immediate action on an email, just calendar it for future action. Remember, we want to use a calendar, not a to-do list.

I'm not against to do lists but I like the calendar approach as well.