I used to keep that up and thought it essential to survival, but I lost the battle. Instead, I've created alternate methods to make sure I don't miss the important stuff. I use Polymail for most of my email which allows me to snooze emails for a few hrs, days, a month, etc. and resurface them as if they were new at a better time. I also file away very important emails into folders / tags depending on the system so I can find them more easily.