Brute force approach is for the weak, and easelly detected by any modern OS too .....
Installing a key listener on every computer was what I did back in my HS.... People were login in, unaware that their keyboard typing was all registered into a log file... At the end of the day, I had almsot all the logins and passwords I ever needed, from Supervisor's to teachers to fellow high schoolers...
.. but then again, that was a long ass time ago, and DOS/Novel security wasn't really the hardest thing to get by.. 
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