Why strong passwords are a must: Ophcrack
Don't let your computer be compromised. Ophcrack is capable of cracking your windows user password in less than a minute. Ophcrack can also be used to recover passwords on old machines.
http://ophcrack.sourceforge.net
San Diego Computer Consulting and Repair http://www.gaslampcomputers.com/blog
Please only use these tools on computers you own.