When I hear the words, cult TV, I think of older shows.. I don't think series like Lost or Prison Break can be classed as cult yet.
Despite being only 19 years old, I like a lot of older shows, most of them are from the 60's.. The Prisoner, The Man From U.N.C.L.E., I Dream of Jeannie, The Phil Silvers Show (AKA Sgt Bilko).. I also like a few 90's programmes, Quantum Leap and Frasier.
Most people my age haven't even heard of these shows let alone watched them.. I just thank my parents and grandparents for introducing me these classic programmes.
I don't really like many modern shows.. The last one I really liked was the BBC version of Robin Hood.