For me, it has to be Danny Deever. Peter Bellamy had the genius to see that the poem was meant to be sung to that tune (Derwentwater's Farewell) and as a result came up with a far greater song than the original ballad:

For they're hanging Danny Deever
They are marching of him round
They have halted Danny Deever
By his coffin on the ground
And he'll swing in half a minute
For a sneaking, shooting hound
And they're hanging Danny Deever in the morning.

Not a pleasant sight at all, but whenever I sing it I can feel myself on a dusty barrack square in India, with troops formed up in a hollow square.