Isn’t 13 unlucky for some?

It’s amazing what you find when you are browsing randomly through the web. It seems that the number on the back of books (the ISBN) is moving from 10-digits to 13-digits in 2007.

The source of this news actually provides a really good overview of how the ISBN system works, and why it is the way that it is (and now moving to a 13-digit number).