Alright, I've got an Old English riddle for you all:
I war oft against wave and fight against wind,
do battle with both, when I reach to the ground,
covered by the waters. The land is strange to me.
I am strong in the strife if I stay at rest.
If I fail at that, they are stronger than I
and forthwith they wrench me and put me to rout.
They would carry away what I ought to defend.
I withstand them then if my tail endures
and the stones hold me fast. Ask what my name is.