The Atlantic Seaboard's Maritime Trade Show is a fairly small, and probably unknown for the most part, show held at the Providence Convention Hall every two years. If you go to the following website you can preregister for free:
Fish Expo Atlantic ~ April 9-10, 2008 ~ Providence, RI
Should you try to get in without pre-registering, it will cost you $20. I went there two years ago just to see what it was all about. It cannot compare to the sportsman's or boat show, but considering the price (parking only), it was well worth it. They had a lot of stuff to do with commercial fishing such as power trains, engines, of course the DEP was there, and workboats. Sort of a small no frills show. I still remember seeing a manufacturer up there that made windshields for cockpits that had extremely fine embedded wires inside the glass. Unless you stick your nose right up to the glass you would never even know the wires were there. By applying a small voltage to the glass, ice would disappear; it sort of works like a rear window defroster. As always, I would plan on eating out rather than in the convention hall.