Drugs and weapons aren't the only contraband in prisons these days. The latest underground currency among inmates is an item most of us consider harmless: the cell phone. And so far, prison officials are fighting a losing battle to keep inmates from obtaining cell phones and using them to communicate with people both inside and outside prison walls.

In California, home to the country's largest state prison system, more than 2,800 cell phones were confiscated from inmates last year, double the number seized in 2007. But the problem isn't limited to California. State and federal prisons across the country are grappling with what officials say is an epidemic of cell-phone use among inmates.

"The problem has quickly gotten out of control nationwide," says Republican Congressman Kevin Brady of Texas, who in January introduced a House bill that would permit the jamming of cell-phone signals within prison walls. "Criminals are using cell phones even from death row to threaten victims and harass lawmakers. Inmates are making literally thousands of calls from prison."

In Texas, prison officials seized 549 cell phones from inmates in the first four months of this year alone. In California, a prison staff member admitted to earning more than $100,000 last year by selling cell phones to inmates. Prisons in Maryland, Virginia, California and Pennsylvania are using specially trained dogs to sniff out phones hidden inside cells and squirreled away in common areas. Florida and Maryland have instituted tougher penalties for anyone who provides a cell phone to an inmate, and other states are planning to follow suit.

In many prisons, cell phones have become as valuable as drugs, if not more so. In a recent sting operation in Texas, an undercover officer was offered $200 by a prisoner for a cell phone and only $50 for heroin. California officials say inmates currently fork over between $100 and $400 to obtain a smuggled cell phone. It's easy to understand why cell phones command such a premium. Unlike the one-time sale of drugs, an inmate can rent out the same phone dozens of times to fellow inmates.

Inmates sometimes use cell phones to keep in touch with friends and family on the outside collect calls made from inside prison facilities are notoriously expensive. But officials say inevitably cell phones are also being used to orchestrate crimes, harass witnesses, organize retaliation against other inmates and even order hits. A Baltimore man is accused of using a cell phone from prison to order an accomplice to murder a witness. (In March, the accused man's cell was raided and guards found another phone.)

Prisoners plotting escapes have found that a cell phone can be just as valuable as a pair of bolt cutters. "I had an inmate escape from one of my prisons just this week, and guess what he used to get his ride a cell phone," says Richard Subia, assistant director for California's Division of Adult Institutions. "According to our investigation so far, he contacted a girlfriend by cell phone and had her pick him up in one of the local towns. We're still out searching for him."

ITT's Intelligence and Information Warfare division is currently hawking a system called Cell Hound that detects all active cell phones within a prison facility and then displays the location on a computer monitor. The monitoring device can also be used to gather intelligence on other illegal activity among inmates. Last month, a Maryland investigation that included wiretaps on prison cell phones resulted in drug and weapons charges for two dozen people, including four state prison officers.

What do you guys think should be done about this?