It's often extremely difficult even for experts to distinguish between a slick scam and authenticity. Your best protection, therefore, is caution--and following these five simple rules. That said, here are some telltale signs of a "phishing" scam:

• Requests for personal information in an e-mail message. Legitimate businesses will not ask for personal information in e-mail.

• Alarmist messages. Criminals attempt to create a sense of urgency by asking that you act immediately, so you'll respond without thinking.

• Misspellings and grammatical errors.  Obviously, if certain obvious words are misspelled that the legitimate company would never misspell, you're being "phished."

• A slightly altered Web address. Only close scrutiny would reveal the deceptive spelling. For example, www.microsoft.com could appear as www.micosoft.com, www.mircosoft.com or www.mIcrosoft.com.

• If it sounds too good to be true, it probably is. In particular, don't be fooled by an e-mail hoax promising easy money. Learn how to spot and avoid this kind of fraud.