An idea is percolating at one of America's government-sponsored mortgage finance giants that could unlock a huge new lifeline for homeowners, Meredith Whitney wrote for The Financial Times

"As early as this summer, a proposed move could begin to unleash almost $1tn into consumers' wallets. By the autumn, it could be on its way to $2tn," Whitney wrote.

That's if Freddie Mac secures approval from its regulator to operate in the market for secondary mortgages, also commonly known as home equity loans. If greenlighted, the scheme would be equivalent to a huge stimulus injection, but without a cent added to the national deficit, the "Oracle of Wall Street" explained.

Under the plan, Freddie Mac could start purchasing second mortgages and package them into bonds the way it does with primary home loans now. As Freddie Mac is a massive provider of mortgage market liquidity, the move could encourage more banks to extend this financing to customers.