Can I call my hotel/restaurant/hostel etc “Fawlty Towers”?
No, is the strictly legal answer. The BBC own the “Fawlty Towers” trade mark under several Classes which cover all sorts of things including computer games, calendars, clothing, etc. It is understandable, in my opinion, that they should restrict people from creating merchandise and profiting from the show. Class 42 covers use in the following areas: “Accommodation services; catering services; hotel, restaurant, cafe and bar services”, so you can’t [legally] use the name Fawlty Towers in any of those types of business without the permission of the BBC. The link earlier in this paragraph details the full list of goods and services covered by the trademark. There are plenty of establishments around the World using the name Fawlty Towers though.