And then while checking your email you mindlessly click it and realize its the one you have "snoozed" by marking it unread, so you need to mark it unread again.
Now I have a keystroke that will automatically create a TODO with a link to the message. I hit the keystroke and then archive so it no longer shows up in my inbox.
There are lots of poor productivity books/hacks, but the "Do not treat your inbox as a TODO list" has stood the test of time.
Rinse, repeat