I am surprised that noone has yet mentioned the British equivalent - not as HI assumes "tuppence" but "ten pennorth" which appears to come from wartime food rationing (WW1), but also in my extreme youth would buy you a portion of chips.....
So at current exchange rates, does this mean that the contributions of UK resident downers are almost 20 times more valuable than those of their US counterparts?
And well if we compare with Australian, NZ, Canadian and Singaporean cents ... well the situation gets better ..or worse ...