The housing crash has left at least 11 million people in the unenviable position of owing more on their homes than they are worth—and many more millions with properties worth far less than they paid for them.

But some might not be as trapped as they think.

Record-low mortgage rates and a new slump in home prices are presenting unusual opportunities in the housing market these days—even for so-called underwater borrowers.

Larry and Mary Schuck paid about $29,000 to refinance into a 15-year mortgage at a rate of just 4.5%. That's like an investment return of about 10% a year over five years. They also reduced their total interest payment by more than $95,000.
Some intrepid homeowners are intentionally taking a loss on their current house—and writing a big check to retire their old mortgage—in order to buy twice the home for not much more money. Others, eschewing conventional personal-finance advice, are even opting for "cash-in" refinancings, paying thousands of dollars out of pocket to settle old loans—and then taking out new mortgages with lower payments, shorter durations or both.

The attractive terms are spurring people like Scott Ayler, 35 years old, into action. He and his wife, Jaclyn, 33, recently decided to trade up to a larger home in their native Denver, despite taking a loss on their current house. In 2004, they paid $234,000 for a three-bedroom, 2½-bath house built that same year in Green Valley Ranch, a subdivision that has among the highest foreclosure rates in the city and lacks upscale amenities. They are in contract to sell the home for about $204,000.

Their new home, built this year, cost about $323,000, comes with four bedrooms and three baths, and sits on a corner lot overlooking a reservoir. The house, which was initially listed at $379,000, is in Denver's desirable Cherry Creek area, known for excellent schools, plentiful amenities and few foreclosures.

With $195,000 remaining on their original 6.625%, 30-year fixed-rate loan, the Aylers estimate their total paper loss will be around $45,000. They are putting down only $11,500 on the new house. But because the new FHA loan carries a 4.5% rate, their monthly payment will rise by only $290 a month.

They say they expect better price appreciation in their new home. And with a young daughter and plans for another child, they need more space anyway.

"We don't want to wait for the market to come back," says Mr. Ayler, general counsel for an energy company. "We wanted a better quality of life now."