As a result of various holidays over the years we had accumulated quite a lot of Euro notes. When the Greek saga started we had a bad feeling and rid ourselves of them. This was fortunate as we found that with the pound being weak at the time our return was better than we had paid for them (less inflation and interest of course!!) and a small profit was made - even with the original and subsequent costs of exchange. It's not often we are so lucky.
Selling them now would be more painful.