One of my favourites is 'The Mermaid':
It was Friday morn, when we set sail, And we were not far from the land. When the captain he spied a mermaid so fair, With a comb and a glass in her hand.
And the ocean winds do blow, And the stormy seas do roar, We poor sailors are skipping at the top, While the land lovers lay down below, below, below, While the land lovers lay down below....etc.
The whole song should be in the DT but the Clancy Brothers do a good rendition of the song, as do many others. Another good one is 'Hey Haul away, hey haul away Joe'. The Clancy's do that one too.