On the freezing, windswept streets of Iceland's capital, there is little evidence that a motley crew of computer hackers and anarchists could soon form its next government.

As elderly couples and swarms of tourists amble around Reykjavik, not a single outdoor canvasser or campaign poster is in sight.

But inside the headquarters of the Pirate party, which lurks by the harbour, dozens of volunteers are hammering on keyboards as they spread their anti-establishment message on social media - which they say is where the real election battle is being fought.