check out sQuidd.io, a new site for sailing enthusiasts:
You can find marinas, harbors anchorages and other great sailing destinations pretty much anywhere in the world. Can't find your favorite spot on the map? You can add it for other sailors can see it. You can also post your coordinates by satellite phone or iphone, so your friends can see where you are. If you are part of a boating fleet or regatta you can view other sailors positions on an map!