http://forum.lessthandot.com/viewtopic.php?f=102&t=9810

The password in the site was case insensitive and recently is has changed to case sensitive.

The question is - if you know the letters/numbers of your password, but don't know what case each letter was, how many combinations should you try to log in correctly.

One extra credit question. How many users (and in percent of the total number) would not be able to figure this out and abandon the site because of this change.