[Btd] The "Warsaw Concerto" was written by Richard Addinsell for the film "Dangerous Moonlight" and, whatever its merits, has nothing to do with Tchaikovsky or even Rachmaninov. I think you mean the B flat minor concerto, but I don't think it is. I had no idea that you'd all find my little snippet so hard. Shall I reveal all, or take three more guesses?