Be nice kids.
First of all, and I have to say this because of some recent comments, this is not a virus, and will not delete any files from your computer. In fact, ophCrack, the software we're gonna use is a very popular password cracker. Google it or Wikipedia it if you don't believe me.
This works for WINDOWS ONLY
UPDATE: WORKS FOR XP AND VISTA
This will crack all windows passwords up to 14 digits on a computer.
You need physical access to the computer.
You don't need to be logged in (that's what this is for).
It will tell you all user names and passwords on the computer.
Step 1: Get the resource
2. Download the latest version of ophcrack live cd. To crack passwords on an XP computer select 'ophcrack XP LiveCD'. To crack passwords on a VISTA computer select 'ophcrack VISTA LiveCD'.
3.The software you download will be a CD image (.iso format). If you try opening this on a computer with a CD-Writer and CD-Writing Software (eg. Nero, Roxio, Record Now, or whatever you have) it will write that file to a CD.
So, make the CD