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U.S. Fed Chairman Ben Bernanke's pessimistic testimony to Congress on Thursday has caused increased handwringing around the world, with new reports questioning whether the subprime fallout will lead to a worldwide recession. The general consensus is no — the damage will be contained to the housing sector and hedge funds, which irresponsibly invested in subprime.

But what if subprime's use were actually more widespread? Some mutual funds have acknowledged small investments in the funds. This isn't a big deal, as some risk is to be expected in those vehicles. But what about money-market funds, where most personal savings are invested? They offer a low rate of return and are considered one of the safest investment. But according to a recent Bloomberg article, money-market fund managers have invested $11 billion in subprime, including managers at Bank of America and Morgan Stanley. In other words, about $11 billion worth of personal savings are at risk.

In the grand scheme of things, $11 billion is a drop in the bucket. But as we've seen over the last few months, small problems like this tend to be more widespread, so it's likely more money-market funds will be forced to acknowledge subprime investments, and peoples' savings, which are already at historic lows, could disappear. If this happens, recession would be inevitable, and depression a real possibility.