Share 'Single Greatest Pub song ever?'

All right, since i just found the button to post a topic, as it was in white ON WHITE... heheh I want to pose the following question to the rest of you. Whats the single greatest Pub song ever? What song is it, in your opinion that is so infectious that the whole place instantly starts clapping and singing? i'll save my answer for further down th thread, just to see what others start saying...:)