Such vitriol! Can your currency code handle sea shells? It should! :)
I only mention it because the yen thing surprised me once as a newbie programmer. (A tip: "%0.2f" is no substitute for actual i18n.) It never hurts to be aware of the edge cases.
The yen has no fractional units (anymore), so when I added support for that currency but continued to use the same format string as all the others, prices like ¥1000.00 looked unnatural.
The historical subunit of the yen is the "sen" (銭), which you often seen mentioned in prewar books. Postwar inflation made sen-denominated currency obsolete, but...
[A bit of googling also turns up the "rin" (厘), which is a thousandth of a yen...]
I only mention it because the yen thing surprised me once as a newbie programmer. (A tip: "%0.2f" is no substitute for actual i18n.) It never hurts to be aware of the edge cases.