Several weeks before I left on my trip I went to the bank and bought some British pounds and some euros. I had plenty of cash with which to have fun!
Denmark, Sweden, and Russia don't use those currencies, though. I didn't buy anything in Russia except to pay for my shore excursions, and I charged what little I bought in Sweden and Denmark. For one purchase in Denmark I could use euros but was given change in Danish kronur, which was no problem at all.
By the time I got to Iceland, though, I had 100 Danish kronur and well over 100 euros in notes, plus miscellaneous coins in those currencies and British pounds. I exchanged all the notes to Icelandic krona upon my arrival in Reykjavik. I started with about 27,000 krona, the equivalent of about $200.
It's hard to explain how expensive Iceland is, even when compared to other Scandinavian countries. T-shirts in souvenir stores routinely sell for $30 or more. Restaurants listed prices around $50 for average fare. The $16 I paid for some fish and chips, which doesn't seem too outlandish, included two small pieces of fish and enough fries barely to fill a salsa bowl at a Mexican restaurant back home. Gasoline was in the $7-8 dollar a gallon range, not too far off of Northern Europe. Icelandic wool sweaters--made from one of the few things that doesn't have to be imported into that country--were in the $150 range. The cheapest pair of wool socks was $16/pr. Even the smallest of books could fetch $30.
The bottom line is that it wasn't going to be hard to spend 27,000 krona in just under 4 days. In fact, had I gone to the Blue Lagoon (don't ask) I could have polished off most of that in one fell swoop. (BTW, the smallest vial of algae from the Blue Lagoon at their store in Reykjavik could have used up most of that money.) Anyway, I like to buy things for people back home--shot glasses, Christmas tree ornaments, candy--and by the last day the money was running low. I had done a pretty good job of spending the money down--I didn't want to have to bring any of it home, as I'd probably never get to spend it again. And by the time I got to the airport, I was down to a few hundred krona remaining.
"Traditional Icelandic chocolate" bars. Hm. Traditional? Were the original settlers growing and processing cacao contemporaneously with the Aztecs? No matter, who wouldn't like a chocolate bar? I bought a couple.
I spent my money well, coming home with exactly 4 krona.
There are roughly 130 krona to the dollar.