Previously this list was in alphabetical order, but in hopes of making it more useful, I rearranged it. Coast Guard sites are listed first, then non-Coast Guard sites. Within those two groups the sites are arranged based on my perception of how active they are in terms of the frequency with which new material is posted from most active to least, with my perception of how relevant it is to our readership thrown in as a fudge factor.
Eaglespeak (great source for information on piracy)
MarineLink (Shipping/Marine Industry)
MarineLog (shipping industry and shipbuilding)
gCaptain (Shipping industry)
Cdr Salamander (Navy news)
Covert Shores (among other topics, drug subs and other craft used for smuggling)