As a close friend of the twins Erin Junkans says you always need to be alert because you never quite know how people are going to react or what they are going to say.

BBC: Living a conjoined life

But as I've said, backs are tricky and we never know how exactly they're going to react.

WSJ: Yankees INF Youkilis happy with back prognosis

That sounds suspiciously like the Fed's position before and after the stockmarket bust: sit back as the bubble grows, but react aggressively in the aftermath and never mind criticism that the low interest rates of a few years ago helped to stoke the housing bubble.

ECONOMIST: Economics focus

And they simple don't know how the ECB would react - whether it would do something that central banks are never supposed to do, which is provide unsecured loans, or whether it would allow the bank to fall over, and risk a chain reaction of collapsing banks.

BBC: Business

When a weather crisis hits New York, you never can predict just how the Big Apple or its millions of residents are going to react.

FORBES: Come on Irene...