I'll go with a Top Ten, since it has been a great two decades for television:
1) The Wire
2) Deadwood
3) The Americans
4) The Crown (still in progress)
5) Justified
6) Hannibal
7) Breaking Bad
8) Spartacus (STARZ)
9) Curb Your Enthusiasm (still in progress)
10) Penny Dreadful
Honorable...