Virgin Mobile also launched a service called "Pink Slip Protection" that waives up to three months of monthly charges if a customer becomes unemployed.

According to Virgin Mobile, the new services are geared toward cost-conscious consumers looking to pare down cell phone service bills in the face of a weakening economy.

Dropping the price on its unlimited calling plan puts Virgin Mobile on par with competing carriers that have started offering similar nationwide plans. Some carriers, such as MetroPCS and Leap Wireless, offer unlimited prepaid plans that range from $35 to $50. And Sprint, which lends its network to Virgin Mobile, offers a $50 prepaid plan with its Boost brand. Virgin Mobile falls short, however, offering only unlimited calls for $50, while the other prepaid carriers tie data into their unlimited packages.

"This offer allows us to effectively compete in the market and we believe will help to further improve our financial performance," Virgin Mobile USA CEO Dan Schulman said in a statement.

With Pink Slip Protection, Virgin Mobile aims to reduce the monthly burden of bills as unemployment rates skyrocket.

"With the unemployment rate rising, the fear of job loss or salary reductions have made consumers watch every dollar," Schulman said. "These issues tend to impact our prepaid base more than many wireless users, so we hope this program can offer some peace of mind to our customers."

The new $50 unlimited calling plan does not require a contract and also carries no activation fees, long-distance or roaming charges and can be paid with cash or credit and debit cards. Along with the unlimited plan, Virgin Mobile updated other monthly plans, offering 300 anytime minutes and 1,000 night and weekend minutes for about $30, and 400 anytime minutes and unlimited nights and weekends for roughly $40.

All of the new plans can be bundled with text messaging and/or mobile Web access for as little as $5 each monthly. Unlimited messaging is a $10 monthly add-on.

New customers who sign up for any of the three new plans are automatically enrolled in the Pink Slip Protection program. The program kicks in after two months. If a customer becomes eligible for unemployment benefits within the next 12 months, Virgin Mobile will cover the cost of the monthly plan, plus taxes and surcharges, for up to three months, though customers must present eligibility for state unemployment benefits.

Open enrollment into the Pink Slip Protection program is available to current prepaid monthly plan customers who have been signed up for at least two consecutive months through June 30.

Along with launching new plans and Pink Slip Protection, Virgin Mobile on Thursday unveiled a "Texter's Delight" program, a nationwide prepaid service for "heavy texters" that offers 1,000 messages for $15 or unlimited text and messaging for $20. Those plans include text messages, instant messaging, e-mail, photo messaging and video messaging.

Virgin Mobile said the new plans and the Texter's Delight service go into effect April 15.