Good morning, dear readers. If you haven't finished your holiday shopping yet, check out the first item below for a last-minute gift idea.

Money talks, cash is King

What's the most economically efficient Christmas gift? Ask an economist, of course. Mark Perry explains on his Carpe Diem blog: "The best outcome that gift-givers can achieve is to duplicate the choices that the gift-recipient would have made on his or her own with the cash-equivalent of the gift," Perry writes. What are the odds that you will be able to intuit little cousin Johnny's most desired object? Not great. It turns out that buying the relatives something, because cash is so gauche, results in an "economic 'deadweight loss' of between one-tenth and one-third of the retail value of the gifts purchased." Just think about the time and energy you'll save, not to mention giving Johnny the perfect gift, by sticking with cash.

More encomiums for Bernanke

As the Fed concludes its final meeting of the year today, the Wall Street Journal's Jon Hilsenrath looks back at Ben Bernanke's time at the helm of the central bank during the worst financial crisis since the Great Depression. Criticized for the extraordinary measures he took during the darkest days, Bernanke seems to be leaving amid praise for the way he responded to (not anticipated) the near-collapse of the financial system. Yes, growth to date has been disappointing. "But disappointing relative to what it would have been absent everything the Fed did?" asks Carmen Reinhart. "I doubt it."

Hold the presses on that death spiral

The Washington Post's Sarah Kliff, citing a Kaiser Family Foundation report on the Obamacare death spiral, says everyone's worst fears won't be realized if young adults don't rush to enroll on the health-care exchanges. Even if younger enrollees make up only 25 percent of the market, compared with an anticipated 40 percent, it will only raise premiums by a few percentage points, according to the study. Age is important, just not super important, they conclude. A few percentage points may not sound like a lot, but when you throw in what's expected to be small-business sticker-shock next year, it will add up to another broken promise from President Obama.

Yes, the U.S. fiscal situation is unsustainable

The Congressional Budget Office just updated its long-term projections for Social Security. Here are the highlights. In calendar year 2010, annual Social Security revenues fell short of annual outlays for the first time. In fiscal 2013, Social Security outlays totaled $808 billion, almost one quarter of the federal budget. The gap keeps growing. As the baby boomers retire, outlays increase as a share of GDP while the revenue share remains constant. By 2030, outlays will exceed revenues by 30 percent. You get the drift. The two lines -- spending and revenues -- grow further apart in perpetuity. This is why the U.S. needs to slow the growth rate of entitlement spending now so the government doesn't have to slash it in the next two decades.

No "waste not, want not" for Uncle Sam

Senator Tom Coburn of Oklahoma is out with his Annual Wastebook. It's always fun, or depressing, to see how recklessly the federal government spends someone else's money. Consider some of the highlights: $7 billion for the Defense Department to destroy useable vehicles and other military equipment; $400 million for government employees to do nothing; $500 million for USDA loan guarantees for the purchase of beach houses in places like Hawaii and Paradise Island (no down payment required); and $914 million for the "Popular Romance Project" to explore the influence of romance novels -- from a "global perspective," of course.

(Caroline Baum is a Bloomberg View columnist. Follow her on Twitter.)