Want to annoy a Yesser?

Then equate their indyref campaign to the anti-Westminster, anti-politics of UKIP.

After all, nothing gets the backs up of Scottish nationalists quite as much as being compared to British nationalists.

They have a point. The SNP - to its credit - shrugs off anti-immigrant sentiment that, recent polls confirm, is every bit as strong north of the border as south.

And Scotland's main pro-independence party has little time for Euroscepticism - despite a substantial anti-EU following of its own.

But, their very different ideologies aside, both SNP and UKIP draw much strength by tapping into public disdain of "Westminster", of expense-guzzling, soundbite-giving mainstream politics; of bankers and austerity; of perceived greed and hypocrisy.

They aren't the only European parties to do so. Take Iberia.

In Spanish-speaking Spain the big beneficiary of such sentiment has been a new flash movement called Podemos. In Catalonia, the winner has been SNP-style nationalists Esquerra Republicana.

Unlike UKIP and the SNP, these two movements detect some common ground.

First up, Podemos. This is not quite the UKIP of Spain. It's populist, yes. And a little Eurosceptic too.

But the party - the Spanish name translates as "We Can", is more left than right, even if its leader Pablo Iglesias rejects such labels.

Forged in the anti-austerity, anti-corruption Indignados protests of 2011, Podemos is now on track to win this year's Spanish general election with, the polls suggest, just under 30% of the vote.

Its attitude to Catalan independence? Well, it believes the people of Catalonia should decide. That may not sound to radical to British ears.

But as Madrid politicians blocked a referendum in Catalonia, Podemos declares Scotland's big vote to be an "example of political and democratic normality".

Anti-politics is booming in Catalonia too.

Esquerra - like the SNP a centre-left party - has grown in the polls just as the traditionally centre-right regionalist parties of Catalan President Artur Mas lose ground.

In fact, Mr Mas's CiU alliance has its own equivalent of the corruption scandals in Madrid that have undermined public support in the old political system much as the expenses row did in the UK.

Lluis Llach, the singer-songwriter whose 1968 hit L'Estaca became the anthem for freedom movements first in fascist Spain and then in Communist eastern Europe, sees huge parallels between the independence and Indignados movements.

The passionate Catalan nationalist said: "Podemos and us are, in reality, two distinct responses to a chaotic state of the perversion of democracy."

The nearest Britain has had to a major cultural figure linking anti-austerity sentiment in England to the SNP is Billy Bragg. But Llach isn't just a Bragg. He's an iconic artist of huge historic significance. And he has a big point.

Together Podemos and Catalan nationalists could tear apart Spain's political establishment. Not quite together, UKIP and the SNP could do the same. Both the UK and Spain have general elections this year. Both states - western-Europe's main multi-national polities - look like having a tough 2015.