However, the cat (or, rather, subatomic particles that behave like the cat) has proved hard to hunt down in practice because such superpositions of states are fragile and easily disrupted phenomena.

ECONOMIST: The 2012 Nobel prizes

Meanwhile, back at the Cheshire Cat boutique, the Comstocks are hard pressed to name all of the tax forms they have to file.

WSJ: Help Wanted: Tax-Compliance Gurus

It's kind of hard to tell whether the new Aibo is supposed to be a dog or cat.

FORBES: Ten O'Clock Tech: Sony's New Aibo Robot Pet

Predicting what people will think is funny is hard to do, but there always seems to be massive interest in the latest popular cat video.

FORBES: Cheezburger's Ben Huh: Content Will Be Short, Interactive And LOLworthy [SXSW]

It is hard now to believe that in 1902 a tiger was shot under the billiard table (that the big cat emerged from a circus rather than virgin rain-forest, and was shot by a school headmaster, makes the story no less exotic).

ECONOMIST: Pukkah hotels