* This is a utility to (re)set the password of any user that has a valid
  (local) account on your NT system.
* You do not need to know the old password to set a new one.
* It works offline, that is, you have to shutdown your computer and boot off
  a floppydisk or CD.
* Will detect and offer to unlock locked or disabled out user accounts!
* It is also an almost fully functional registry editor!

WWW: http://pogostick.net/~pnh/ntpasswd/