I spent three solid semesters wasting my "Computer Science" electives on breaking into the Novell system... I found tons of these encrypted passwords, and it never occurred to me to just crack one. I did find plenty of other ways to get in, though :)
They had had a bad break up with another supplier and had lost access.
I used our Art directors MAC to break in - I did consider setting up a diy cracking farm using all our suns and running it over night but I suspect that the security department might not have approved.
NT hashes use MD4, which wasn't invented until 1990.
L0pth Crack utilized this when cracking, it first found the uppercase password, then it only had to brute force the case when cracking NTLM.