bothering and needing is different!
yep, as eggman said if your recieving the usual channels(terresterial or digital, typical TV, freeview type box, or PC/laptop adaptor) you need to get a TV license or your breaking the law.
Though from what I hear a good number of people don't and they risk it. I've read about many of the technicallities. Like they can't come in unless you let them(or your cleaner/flat mates/landlord) or they have a search warrant. - Though not being let in is good suspicous reason to get a warrant. And the equipment has to be set up (e.g. no arieal plugged in if you just watch videos).