I've been meaning to give Yesterbox a try for a while. The general idea is that each day you only deal with email that arrived yesterday or earlier. This forms your inbox for the day, hence "yesterbox".

Once you've emptied your yesterbox, or at least got through some minimum number (10 is recommended) then you can look at emails from today. Even then you only really want to be dealing with things that are absolutely urgent. Anything else can wait til tomorrow.

The motivation for doing this is to get away from the feeling that we are King Canute, trying to hold back the tide. I find that when I'm processing my inbox toward zero there's always a temptation to keep skipping to the new stuff that's just come in. Hiding away the new email until I've dealt with the old is a very interesting idea.

I use mu4e in emacs for reading my email, and handily the mu search syntax is very flexible so you'd think it would be easy to create a yesterbox filter:

maildir:"/INBOX" date:..1d

Unfortunately, 1d is interpreted as "24 hours ago from right now" so this filter misses everything that was sent yesterday but less than 24 hours ago. There was a feature request raised on the mu github repository to implement an additional date filter syntax but it seems to have died a death for now. In the meantime, the answer to this is to remember that my workplace observes fairly standard office hours, so that anything sent more than 9 hours ago is unlikely to have been sent today. The following does the trick:

maildir:"/INBOX" date:..9h

In my mu4e bookmarks list, that looks like this:

(setq mu4e-bookmarks
      '(("flag:unread AND NOT flag:trashed" "Unread messages" ?u)
        ("flag:flagged maildir:/archive" "Starred messages" ?s)
        ("date:today..now" "Today's messages" ?t)
        ("date:7d..now" "Last 7 days" ?w)
        ("maildir:\"/Mailing lists.*\" (flag:unread OR flag:flagged)" "Unread in mailing lists" ?M)
        ("maildir:\"/INBOX\" date:..1d" "Yesterbox" ?y))) ;; <- this is the new one