Do people know about Alive and Kicking Lobsters in Cambridge? It's at 269 Putnam Ave., right off River St., on a residential block, in a converted house. They sell some fresh fish and shellfish--and lobster rolls for $9. They're served on toasted bread (not a hot dog roll), and they're chock full of lobster meat, only lightly-dressed. (I just called the guy who owns the place and he got offended when I called them "lobster rolls." "They're lobster-salad sandwiches!" he insisted). They're really good. And the store just put out a couple of picnic tables to the side of the building.