There are litrally thousands of them; I'm sure the Roman soldier guarding Hadrian's Wall was singing them - he was certainly scrawling graffitti.
My favoirite (seldom sung) verse is from the arch-type of the genre, 'Browned Off' .

The medical inspection, it is a bleedin' farce;
They grope around your bollocks and they finger up your arse,
For even a private's privates enjoy no privacy.
You sacrifice all that to save democracy.

Chorus:
For I was browned off, browned off, browned of as can be,
Browned off, browned off; an easy mark, that's me.
But when this war is over and again I'm free,
There'll be no more trips around the world for me.

Jim Carroll