Not exactly a folk song (or is it) but one which I have enjoyed singing as the bass singer in Das Trio with Maike Weyerts and Britta Steenken (both sopranos). The song has text phrases from Stormalong and I especially liked the bit where "Willy what got drownded [sic]" in the deep blue sea of course. Great fun!.
The SAB arrangement (choral: Pat Shaw; piano: Eugen Bersenkowitsch) we sang can be found in Chor aktuell junior published by Gustav Bosse Verlag

Lyrics