Yeah. I love the idea of a single currency. But I think it has serious drawbacks. Having the same currency across the UK meant that a prosperous financial centre in London made a northern manufacturing centre much less likely. Having the same currency across Europe seems to be causing all sorts of imbalances there.

I don't think that a single currency can be successful in the long term without much more political union. And the current situation makes things more likely to fracture than unify.

Schengen, on the other hand, will be awesome.