[bunderbunder]

The United States already handles this just fine. So easily that folks don't really even notice, in fact.

Ever notice how gas stations usually give prices out to 1/1000 of a dollar (e.g, $3.459/gal) even though our smallest currency denomination is for only 1/100 of a dollar?

It happens with sales tax, too. In Chicago, the tax on a $29.99 video game is $2.924025. We'd just round down to $2.92, and the government lets that odd 0.4025¢ slide. It doesn't really add up, because there's also cases where the tax owed is something like $2.925975 and gets rounded up to $2.93.