You can find a program that lets you purchase those TV shows then look for a device they are good with syncing. It's still hard to find stuff for TV shows though.
There's also the 605Wifi that can directly purchase or rent TV shows and Movies through the Wifi but I'm guessing from your chose of the Zen and Nano you're looking for something small and flash based?
I had fully intended to purchase the Creative Zen until I realized that the reason I am upgrading from my V Plus is b/c: (a) the screen is only 1.5" and (b) I want to watch videos on it. By going to the Zen I will take care of the screen but I am not sure about the videos; the things I prefer to watch I would generally rather purchase in episode form rather than a whole season and I am currently unaware of anything that will allow me to do this for the Zen. Which ultimatly is what is making me consider the iPod Nano or Classic whom I have nothing against its just that I don't like having the same thing everyone else has and walking around like robots. But the switch seems inevitable once considering the options, and it also seems as if iTunes has the world on "lock" as far as music organizing software and I like watching tv shows, movies, and videos on my mp3 player but I prefer to buy them legally and I am not sure if any other program has such an extensive catalog of tv shows, etc. for portable device use. If anyone would happen to know of another website, program, etc. that I can get as many (if not more) shows, movies & videos for viewing on my mp3 player please post a response with it.

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