To help against impersonators, Facebook will allow users to register their computers.

With the recent wave of bad publicity stemming from its controversial measures related to its privacy policy, Facebook can benefit from any act seen as good will. A series of new features introduced by Facebook last month, failed to get the same kind of attention that its tinkering with its privacy got. One of those features has the potential to be of great help for users to guard against impostors and cybercrooks who may take over their accounts with very bad intents. The feature will allow users to register a list of "approved" devices -be it a home or work computer, a mobile phone etc- that they will be using to access their Facebook accounts and when someone try to access their accounts from an unregistered device, an alert will be sent to them via e-mail or text message.
If it happens that they were not the one trying to log in, they will be instructed on how to remove the unauthorized device and reset their passwords.
The new feature can be accessed from the "Account Settings" page and is easy to set up.

For more, see NewYorkTimes.com