Telephone Service Information about calling cards, toll calling, long-distance calling, cell phone radiation shields and computer-based telephone services. Long Distance Long-Distance Helpful information to sort through various long-distance "deals."   Computer Technology and Phone Calls Computer-based Calls   Avoiding long-distance charges on your modem. VoIP: Voice Over Internet Protocol Understanding this new technology, including possible benefits and limits to service, equipment needs, and privacy and security issues.  Toll Calling 900 Numbers FTC's 900 Number Rule, outlining necessary disclosures, exceptions and how to handle billing disputes. Calling Cards Pre-Paid Calling Cards A brief look at a few avoidable problems with these popular calling cards. Telephone Service Fraud & Scams International Telephone Number Scams How best to avoid being taken in by costly international telephone number scams, including specific tips for identifying authentic international calls. Messages Tips for recognizing costly telephone traps masquerading as genuine messages. Cramming How to recognize a phone bill "crammed" with extraneous charges and how to avoid them. Unauthorized Charges Understanding how to get refunds from unauthorized phone charges, including terms and conditions for disputing 900 numbers. Cell Phones Radiation Shields Important information regarding so-called "radiation shields" for cell phones.