As many as 20 million Americans may have unauthorized charges hidden on their land-line telephone bills, the Federal Communications Commission estimates.    This practice of \"cramming\" charges, typically from $1.99 to $19.99, for unauthorized products or services onto monthly statements often goes unnoticed … for months, says FCC Chairman Julius Genachowski. \"Consumers too often get bilked out of hundreds of dollars.\" Genachowski today plans to propose that the FCC craft and adopt anti-cramming rules. \"This is both about making sure consumers aren\'t getting ripped off and also about fostering trust in communication services,\" he says. \"Practices that hurt the trust and confidence consumers have in communication services are bad for our economy.\" The FCC and Federal Trade Commission stepped up their investigation of cramming in recent months after complaints to the FCC jumped, Genachowski says. For every victim of cramming, there are perhaps another 19 who don\'t notice that they are being victimized on their bills, the FTC found. Phone service providers and third parties are typically the culprits, often improperly charging for voice mail or long-distance services. Genachowski cited as an example a St. Louis woman who was charged for 25 months of long-distance service she never authorized or used. \"We\'ve seen people getting charges for yoga classes, cosmetics, diet products, and, yes, psychic hotline memberships,\" he say. \"These mystery fees are often buried in bills that can run 20 or so pages, and they are labeled with hard-to-decipher descriptions like U-S-B-I.\" The investigation resulted last week in the FCC issuing $11.7 million in fines to four Pennsylvania-based companies: Main Street Telephone; VoiceNet Telephone; Cheap2Digital Telephone; and Norristown Telephone. The Senate Commerce Committee plans a hearing on cramming and will soon issue a report on the practice, says the panel\'s chairman, Sen. Jay Rockefeller, D-W.Va. The FCC launched a tip sheet at www.fcc.gov/consumers and urged consumers to review their bills every month, and report discrepancies to their phone company. \"We all want to send a clear message: If you charge consumers unauthorized fees, you will be discovered, and you will be punished,\" Genachowski said.