General Motors was in the news over the weekend before the largest bankruptcy in U.S. history (that is, its own), but more worrying for many policymakers, economists and ordinary borrowers is last week’s sudden spike in mortgage interest rates. For the last few months, the Federal Reserve had used its considerable clout to drive mortgage rates to practically their lowest level since the introduction of Arabic numerals to the Western world, but movement in the bond market struck back last week, pushing rates from about 4.875 percent to about 5.5 percent. In an effort to whack that interest-rate mole again, does the Fed now buy residential mortgage-backed securities even more aggressively now, on top of the half-trillion-dollars’ worth it has already? There’s a strong incentive for the Fed to do so, as low interest rates are a key component of putting a floor under the housing market, and which have also encouraged a rush of refinancing among homeowners. The details of another strategy for getting homebuyers off the fence was unveiled by Housing and Urban Development on Friday, one that would allow borrowers using Federal Housing Administration financing to apply their federal tax credit toward a home’s purchase price, thus monetizing the tax credit. HUD’s intention to do so was announced some weeks ago, to the thrill of homebuilders and brokers. But the devil emerged from those details on Friday, at least as far as homebuilders and brokers were concerned, since under the new rules, homebuyers cannot monetize the tax credit to come up with their mandatory minimum 3.5 percent FHA loan down payment, but rather for closing costs or to boost their down payment over that 3.5 percent level. The housing industry may be disappointed by that, but there’s a certain logic to not selling houses to people who can’t come up with a down payment of that relatively small size. In their eagerness to sell homes, a certain amnesia about lending practices in the mid-2000s seems to have set in. When will that choice bit of real estate on the North Side of Chicago at 1060 W. Addison (known as Wrigley Field) finally change hands? Tribune Co. chairman Sam Zell, known for his nimble real estate dealings–the sale of Equity Office Properties at market’s peak ought to be a B-school case study in extreme good timing–has something of a dilemma on his hands with the lackluster Tribune Co. The newspaper publisher has owned the Cubs and its 1916-vintage baseball field since 1981, but Zell has made it clear that the team has no place in a future Tribune Co. lineup. Early this year, a deal was struck to sell the team and the ballpark and other assets to a North Shore billionaire family headed by Tom Ricketts, who made their dough in discount stock brokerage, for $900 million. But for the moment the deal is reportedly bogged down in how to value the broadcasting contracts associated with the team. On Friday, Wall Street seemingly couldn’t make up its collective mind about things, and spent most of the day seesawing around the break-even point. But toward the end of the trading day, the Dow Jones Industrial Average moved up 96.53 points, or 1.15 percent. The S&P 500 ended up 1.36 percent, and the Nasdaq was up 1.29 percent.