Anything that helps to make the daily deluge of e-mail more effective is worthwhile.
Stever Robbins offers some ways to make e-mail more effective.
This suggestions will go down well with your boss 🙂
If you are constantly copied on things, begin replying to e-mails that aren’t relevant with the single word: “Relevant?” Of course, you explain that this is a favor to them. Now, they can learn what is and isn’t relevant to you. Beforehand, tell them the goal is to calibrate relevance, not to criticize or put them down and encourage them to send you relevancy challenges as well. Pretty soon, you’ll be so well trained you’ll be positively productive!
Footnote:
Link courtesy of the excellent Online Business Networks blog.
Murphy's Law 