'Are there any Europeans on webdiplomacy who aren't against the common currency?'
i'm not against it. I'm also not against regional/national currencies, or dual currencies.
Cuba operates under a dual currency system, so there is at least an proof of concept in a modern context. Living in Bristol, i found the local Bristol pound to be a very interesting idea.
No serious politician would talk about leaving the Euro for fear of the massive impact it would have on their own economy, just the idea that it was likely could shake the markets and lose people jobs.
In reality, it is business owners who care the most about the currency - i'm sure many worried about introducing the new currency, but the opportunity of opening up new markets was rather tempting, and worth the risk. The risk of instability rising from leaving the currency union would have little to offset it, smaller market, more friction and uncertainty in trade, along with inflation worries.
Germany could leave without the new Deutsche Mark suffering too much, and allow the Euro to inflate, but then they'd be losing out on the value of all the debts they are owed. While losing competitive advantage against all of their neighbours and main trading partners. So they're stuck bailing out anyone who could pull the whole thing down. (and in principle, i'm not against wealth transfer...)
Personally, I don't really care. And most europeans, if given a vote, might prefer their own currencies, but those who have bought in to the Euro are not all that upset about it.
Regardless this doesn't look like it's going to be a big change for European politics...