Facebook's users are a lucrative target for Internet criminals looking to steal passwords and more. To combat malicious attacks, phishing scams and spam, the online social network is rolling out new security features. First, users can choose to be notified when their account is accessed from a computer or mobile device they haven't used before. To do this, go to “account settings,” then “account security,” then click change. There you can choose to be notified of logins by e-mail or text message. Facebook is also adding a layer of authorization when it notices unusual activity on an account, such as simultaneous log-ins from opposite sides of the planet.