Four-eyes principle for Windows
EditBy: The four-eyes principle dictates that at least two people must witness or approve a certain activity. Organizations use the four-eyes principle to protect themselves from dishonest individuals and mistakes.

ANIXIS FourEyes allows you to enforce a four-eyes policy for local logons on Windows 2000, XP, and 2003. FourEyes only allows a user to logon if another user (the observer) also enters their username and password during logon. you can free download FourEyes 1.10 now.