The government-sponsored Home Affordable Refinance Program (HARP) was created specifically to help those who owe more than their home is currently worth. If that's you, and your payments are up-to-date, you might qualify for the relief you need with a HARP refinance.
Fannie Mae is a government-sponsored entity that is one of the largest sources of home mortgage funding in the US. They've adopted changes to HARP that allow more people to get help. To qualify under the guidelines your mortgage must meet the eligibility requirements of Fannie Mae.