Gilbert's Chowder House has been around a lot longer than the tourists now crawling Portland's Old Port district - fortifying the dockworkers and fishermen through long hard days of fishing and unloading.  Nowadays the working fishermen in hip high waders and camera toting tourists peacefully come together as one for steaming bowls of Gilbert's Chowder.  There are five to choose from: clam, fish, corn, seafood and seafood chili.  Seafood chili is just what it sounds like - chili with clams, haddock, shrimp and scallops instead of meat.