chntpw is a command-line tool by Petter Nordahl (Project Homepage) to reset Windows Passwords. Using a workaround, it can even reset a Domain Administrator's Password.

You can imagine that this small tool can come handy anytime. There is an option to create a bootdisk or a bootable CD, but when you've got Knoppix, why not have this also on board?

I believe chntpw was part of Knoppix somewhen, but has been dropped. I don't understand why. It's not big, it's free (source code also being available) and extremely useful. I understand that you can make your own customised Knoppix CD, but I tried and did not succeed. Anyway, this little program should be a standard for every Knoppix distribution for everyone to help recovering Windows-Installations, don't you think?