the old joke
A traveller who is a huge fan of seafood arrives in Boston for the first time. He leaves the airport and hails a cab. After he gets in, he excitedly says to the cabbie, "Hey, I'm new in town. Can you tell me a good place to go to get scrod?" The cabbie replies, "Pal, I've got to congratulate you. I've heard that question a lot over the years, but that's the first time I've ever heard it in the pluperfect subjunctive."
eta
some nutkin has posted this joke before