Farthings were in use on the UK up until 1960 when they became no longer legal tender. A farthing was a quarter of a penny or 1/960th of a pound. This would be about 1/600th of a US cent at today's rate of exchange, roughly speaking. Eleven pence and three farthings was a popular price for an item when a shilling (12 pennies) sounded too much; just like $9.99 in today's currency. The farthing was also used as a description of a high wheeler bicycle which, in the UK, is still called a Penny Farthing because of the relative sizes of the wheels.
Two farthings made a halfpenny, or ha'penny, which was removed from legal tender in the UK in 1969. Both the farthing and ha'penny had been around for 700 or so years before they met their demise. I can well remember the discussions we would have about how silly and annoying such pittances of coins were especially with the imminent demise of the Canadian cent. I wonder how much longer the US cent has to go? I wonder how many there are in "penny jars".
You could almost study the entire history of Britain by exploring changes in the simple farthing