If you ever get called upon to help friends and relatives with their PC problems, then one of the things you'll need in your virtual toolbox is a collection of password recovery programs. These can be very useful if someone has forgotten a vital password.
Nucleus Technologies offers a range of commercial password recovery programs. However, it recently removed the price tag from some of its products and made them freeware instead. This includes password recovery apps for Outlook, Outlook Express, and more besides. For the full list, see http://www.nucleustechnologies.com/Free-Data-Recovery-Software.html.
As always, though, remember that it's not a good idea to attempt to crack a password unless you have the permission of that password's owner.