The thing about email — and the reason it has become a pest as well as a boon, is that it makes it easy to c.c. messages to many people, thereby transferring cost to the reader. How much cost? Well, suppose you get 50 non-spam messages a day, and you spend an average of three minutes reading and considering each. What’s that in real money?

This very useful piece, “Tips for Mastering E-mail Overload” by Stever Robbins, suggests dividing your annual salary by 120,000 to get the per-minute cost of your time. But this reflects the longer working hours of Americans. For denizens of “old Europe” the rule is: divide by 110,400 (46 weeks, 5-day week, 8-hour day) to find out how much your email costs. The article has lots of really sensible tips — mostly aimed at authors — for making email more efficient. Thanks to Quentin for the link.