I set up a Hulu account and found a number of things that would be interesting to watch. Time is the major problem.
I have trouble watching all of the things I want to see on broadcast TV as it is. I have sometimes gone to the Fox website to catch the episode of House or Bones that I have missed. I have gone to ABC and NBC to catch up on Dancing With the Stars or The Biggest Loser. I like the features at those websites of giving me the highlights of those shows in a brief period of time.
Friends have talked about the show Ruby which is apparently on the Style Network or some other network not available to me on my cable. Apparently it isn't on Hulu or Joost either. This certainly does provide people with another option to watch something they missed or are just interested in.