@bumidan: If it's not very clear please ask.
Assume that 20% of their revenue is from Japan, and 80% from overseas (source).
There's this great tool to get historic exchange rates. The euro->yen dropped 6.6% from the end of 07Q2 to the end of 08Q2, while the dollar dropped around 7.8%. That gives us an average drop of 7.2% between the two currencies.
2007 Q2 revenue: 2083 billion yen
Sales increase in constant currencies: 5% (from the 08Q2 report), or 2187b yen revenue if currencies stayed constant.
20% of this revenue comes from Japan, or 437.4b. The 80% which comes from overseas drops to 1623.6b due to the 7.2% drop in overseas currencies. This gives us a total of 2061b yen, very close to the reported revenue in 08Q2 of 2072b yen. Close enough for me to have some trust that the revenue figures using this method aren't widely off.
Now let's apply this to the holiday quarter. Let's assume flat sales from last year (which is probably optimistic given the recession):
2007 Q3 revenue: 2859b yen
2007 Q3 profit: 200b yen
Drop in the dollar (from Q307 end to today): 15.2%
Drop in the euro (from Q307 end to today): 25.3%
Using the same method as above, we'd get expected revenue of about 2402b yen. Ignoring other factors (see note below), this would decrease their earnings from 200b profit to a 257b loss (calculated as 200-(2859-2402)). That's $2.7 billion.
Note: I know there are factors I'm not taking into account, such as currencies other than the dollar/euro, currency hedging and the recession. That's why I toned down the numbers I expect for losses during the quarter. The point is just to get a rough idea of what to expect, and leave the details to Sony's accountants.