ophcrack a Windows password cracker tool

ophcrack is a tool that can crack windows passwords .

The tool ophcrack uses raibow tables in order to "uncover" LM and NT hashes of the files SAM.

There are two versions of ophcrack . One that runs on live-CD (boot cd before the windows start) and one which has to installed in the victims computer.
You can downlaod both versions from here -->http://ophcrack.sourceforge.net/