Mmm.. Remember the post about hashes..? Well most of the cases passwords in a computer is converted to a hash code before storing them. So even if some one get hold of the password file they are unable to recover the passwords. However there are tools such as rainbow tables to recover them. But these tools take lot of computing powe. Well how about a site doing the same thing online! and for free!
Try this site. It will crack most of the hashes and return the password(s) used to generate them

http://passcracking.com/index.php