My collection:
Norway (1000 A.C., '40s, '50s, '60s, '70s, '80s, '90s, '00s)
Sweden ('70s, '90s and '00s)
Denmark ('70s and '80s)
Germany ('20s, '30s, '40, '50s, '70s, '80s, '90s)
Austria ('90s)
Poland ('90s, '00s)
Thailand ('90s, '00s)
United Kingdom and UK overseas territories ('20s, '50s, '70s, '90s, '00s)
Former Soviet states ('90s, '00s)
States with Spanish-speaking majorities ('70s, '80s, '90s, '00s)
Greece ('30s, '40s, '80s, '90s)
States with Arab-speaking majorities ('70s, '80s, '90s, '00s)
Turkey ('90s, '00s)
Israel ('80s, '90s, '00s)
States with English-speaking majorities (apart from UK) (including USA, Canada, Aus., N. Zeal., etc.) (70's, '80s, '90s, '00s)
Portugal ('90s)
Slovenia ('90s, '00s)
States which former the former Yugoslavia (incl. Cro., B.-H., etc.) (90's, '00s)
Guinea ('00s)
East Asian States (China, Japan, etc.) ('90s, '00s)
Former French colonies (primarily Africa) ('90s)
'International Coin and Money Collecting Card' from Oslo
That's my whole collection, I think. On which areas do I need to improve? Are there any important areas that are missing? I love obscure money, like the Lao kip and the Vietnamese dong (those two will arrive soon).