Aren't a lot of Eastern European mortgages such as those in Poland denominated in Swiss francs? I recall reading about this the last time the Swiss franc was really strong during the financial crisis. If so, the "multiplier" effects of last weeks move could be interesting. Swiss 3mLibor target now at -0.75% middle could pull longer term bond yields into negative territory, maybe not just in Switzerland but also Japan, Germany a possibility. You have to imagine some of the macro "relative value" funds will pile into big short positions in bond markets as yields get close to 0%. I'm myself scratching my head seeing 10yr OATS yielding 0.64% with the Euro currency risk - and I'm pretty open minded when it comes to seeing markets pushing extremes. So I can only imagine how some young trader with an economics degree and a couple of years experience working at a bank is feeling as he throws around his bank's capital, thinking he's the next Soros or Tudor Jones.