I don't want to just post a random circulation coin here (which is why I had nothing for 2019); so for the recent years, I'm trying my best to post either something particularly exotic, or something with at least
some story.
The coin below comes in under the "at least some story" category.

Kingdom of Thailand, Rama IX
25 satang (1/4 baht), 2560 BE (2017 AD)
Rama IX of Thailand (his actual name is too hard to spell) was born in December 1927.
He ascended to the throne on June 6, 1946, at age 18, and died at age 88, on October 13, 2016, after a reign of 70 years and 4 months.
(This makes him the only known monarch so far to have reigned for 70 years without having started "reigning" as a child.
This also means that his entire reign happened between the two most recent World Series appearances of the Chicago Cubs.)
You might have noticed that this coin is dated 2017. (This is, after all, why it is being posted today.)
This means that it was made when Rama IX
had already died. It's a posthumous issue.
...Several more coin types were issued in the name of Rama IX in 2560/2017, but aside from those, I am not aware of any
other posthumously issued coins of the 21st or 20th century.
(There are of course many cases when coins in the name of a monarch continued to be made for the rest of the year of their death - but not, as far as I'm aware, for the year
after their death or later.)