[Callers] Ferry Boat Contra Ideas

Hi Callers, In a couple of weeks, I'll be calling the annual Ferry Boat Contra for the second time. Last year I put a good deal of effort into coming up with nautical themes/jokes, so this year I'll really need to go "overboard." I'd love to hear your ideas regarding entertaining (but not distracting) maritime moves/terminology/jokes/trivia to add into my program. The majority of folks in my area have at least been on a boat other than a ferry, and a number sail regularly, but I'd rather keep the references from becoming too obscure.  Looking forward to your suggestions! Lindsey(Tacoma, WA)