It's an absolute bargain - you have to pay if you have equipment capable of getting live TV. So if you don't watch live TVC, and only watch 'catchup' on i-player you don't have to have a licence.
the fee is per household, so if you are a student living in a dorm,strictly speaking every student should have their own licence (assuming they have a TV in their room!)
People who are over 75 get a free licence, and those who are blind get a discount. If you only have a black & white TV the licence fee is only £50 instead of £145.
The BBC has a charter which requires it to produce a range of programming, which is one of the reasons why we have things like the programmes David Attenborough makes, the Open University etc.
I think £145 for good quality ad-free TV is astonishing value. Other terrestrial channels such as ITV and Channel 4 do get some public funding, but not as much, and of course the TV licence also helps fund BBC Radio (including local radio) But less than 40p a day for things like Doctor Who, Life of Mars, Sherlock, I Claudius, Pride and Prejudice..
Mitch Benn says it best: http://youtu.be/p3q2iZuU5WM
It has to be said, however, that BBC news reporting is no longer the gold standard it used to be.
(I didn't know they were cancelling 'Silk'. Pity,as I like a good laugh.