Here's a quandary almost as old as the paper-or-plastic conundrum: Match or lighter?

While both are exercises in resource depletion, according to Guardian writer Leo Hickman, he concludes that matches are the lesser of the two evils, especially if you can establish where the timber is sourced and the conditions under which the matches are produced. (Here's his admittedly fuzzy math: An average-size aspen yields 1 million matches or the equivalent of 333 disposable lighters.)

Meanwhile, 4 million Bic disposable-and non-biodegradable-lighters are sold worldwide every day, or 1.46 billion a year, all of which will end up in a landfill or incinerator. An average lighter also releases about 0.25 grams of carbon dioxide per minute used. Need more convincing? A lighter's casing, as well as the butane fuel used within, are both products of the big, bad petrochemical industry. ::The Guardian

Difficulty level: Easy