What's your favorite television show? - Networks

Honorable mention: The Voice is a particular favorite of my mothers.
I have watched before and enjoyed it but confess to not being a regular.  It's one of the singing competition shows.  I like it that the judges are typically very positive and encouraging to the contestants.  It's also given me a new respect for Blake Shelton.
Airs on NBC on Monday and Tuesday nights.

Comedy: The Big Bang Theory.
Funny looking nerds are completely my type.  (Please, tell me you already knew that.)  Funny looking smart nerds are even more attractive.  I love that I've seen just enough of the Star Wars, Star Trek and Lord of the Rings trilogies to get all the jokes.
Airs on CBS on Thursday nights.

Sci-Fi: Fringe.
This show is in it's final season with fewer than ten episodes to go.  They will get to 100 episodes and presumably get picked up in syndication.  If you haven't started watching yet, it will make more sense if you start from the beginning (or read the wiki or something). I love the actors on this show.  There's a general consensus that John Noble is the most emmy-snubbed actor in existence and I quite agree.  Sigh.
Airs on Fox on Friday nights (or just DVR it if you're out).

Sci-Fi/Fantasy/Cop Show: Grimm.
I accidentally started watching this show, thinking I was going to find it not interesting and switch channels.  Several episodes into the second season, I'm still around.  Like Fringe and all good Sci-Fi, this will make more sense if you know the back story.  The plots tend to be engaging and the bigger story arcs are also really interesting.  Many of the characters are still enigmas which keeps things interesting.
Airs on NBC on Friday nights (again, use the DVR).

Cop show: Bones.
I refer you to the above comment about smart funny looking nerds. This is one you can pick up in the middle and enjoy it.  Like most of the shows I love, the characters are really engaging and after eight seasons most of them are very well developed (although I preemptively disagree with Cam and Arastu dating).  And there's Booth who is well developed eye candy.  We all need a character we can identify with I guess.
Airs on Fox on Monday nights.  (I want to say it used to be on Thursdays but moved to Monday this year.)

Cop show/Dramedy/Whatever: Castle.
This has been my favorite show since I found it.  I fell in love with the show when I watched summer re-runs and how much the show focused on "this guy doesn't make sense as a suspect because if I was writing the story there would be these three plot holes".  It's like a back door tutorial on writing, characterization and plot development.  Plus, Nathan Fillion and Stana Katic.  Enough said.
Airs on ABC on Monday nights.  Make time.