One From Every Country
(or more correctly, one from every sub-entity!)
An example for each of the 1048 (of 1086) coinage types in my definitive 20th Century OFEC Collection
Note that they are in the same order as on the "20th Century OFEC Entities" page.
(I am in the process of adding images of each coin, please bear with me; in the meantime - get in touch!)

#	Sub-Entity Name	coins from	coins to	Political Designation	ruling authority	Den.	Unit	A.D. Year
0877	Tibet	1909	1910	Ruler Change	Xuantong
0878	Tibet	1880	1953	Independent State		1	Tangka	1907
0879	Tibet	1909	1953	2nd Coinage		5	Sho	1952
0880	Togoland, French	1924	1926	LoN Mandate - France		1	Franc	1924
0881	Togoland, French	1948	1956	UN Trust Territory - France		5	Francs	1956
0882	Tonga	1967	1974	Ruler Change	Tāufaʻāhau Tupou IV	20	Seniti	1967
0883	Tonga	1975	1996	Monarchy	Tāufaʻāhau Tupou IV	5	Seniti	1996
0884	Transnistria	2000	2000	Republic		50	Kopeek	2000
0885	South African Republic	1892	1900	Independent State		1	Shilling	1897
0886	Trengganu	1907	1907	Siamese Malay State	Phra Chula Chom Klao (Rama V / Chulalongkorn)	1/2	Cent	1907
0887	Trinidad and Tobago	1966	1973	British Commonwealth Realm	Elizabeth II	1	Cent	1966
0888	Trinidad and Tobago	1973	1976	Coinage Reform		1	Cent	1976