I had the same idea. ISK/EUR was 0.0032 on monday, so I booked the cheapest flight I could ever get. At least, I thought.

I looked at a currency exchange site which bases it's data upon the data from the European Central Bank (such as finance.yahoo.com). They listed the Icelandic Krona for the last time on Oct 9 and list it as frozen since then.
However, my VISA credit card company charged me more than double ! My transaction took place at 0.0068 conversion. Unbelievable.
Be warned.... credit card exchange rate is bad.