El Tigre

If you can actually make it through the door, order a beer or a cider and marvel at the hefty tapas that come with it – patatas bravas, 'jamón serrano', Spanish omelette... it's all free, and each plate varies (and gets bigger) with each round. The bar itself is incredibly noisy and always absolutely rammed. But it does disprove the theory that there's no such thing as a free lunch.