This plugin was origionally created by ZiNgA BuRgA from http://mybbhacks.zingaburga.com With his permissions I've edited the plugin to improve it.

After activation, this adds two option to user profiles, visible for selected groups:

• Login as this user
  
• Force logout
  

The first allows the administrator to effectively login to the account without the user's password. Everything behaves normally in this login state. The only difference is that logging out will return the administrator back to their original account.

The second option just forces the user to log out if they have logged in somewhere.

For privacy reasons this plugin doesn't allow access to the other's accounts private messages. In most countries this is forbidden by law.