Antimatter: £17bn per gram

In 1999, Nasa said it would cost $62.5 trillion to produce a gram of antihydrogen. Seven years later, it was estimated that a gram of positrons (the antiparticle of the electron) would cost $25bn to make. CERN has spent a few hundred million Swiss francs on producing a billionth of a gram – which would put a gram at a few hundred quadrillion francs.