I tell my sister to stop filling the bath and just get in it but I do the same thing and just ignore her when she points it out. :sweat:
OP, I'd do that as well, like I wouldn't give money away for nothing when I could buy something that would entertain me for years.
I do give change to bagpipe players though because they're just soo EPIC and LOUD!!

It's a standard http://en.wikipedia.org/wiki/ISO_4217 currency code. Usually, the first two letters of such code are the standard http://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 country code of the originating country, and the third letter is the first letter of the (romanisation of) the currency name. Thus, ISK = Islandic (IS) Krona (K), USD = United States of America (US) Dollar (D), JPY = Japanese (JP) Yen (Y) and so on.

Exceptions involve stuff like EUR (for the Euro), precious metals (X + chemical symbol of the metal, for example XAU for gold with the chemical symbol Au), supranational currencies (usually start with X as well) and some other historical stuff.

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