In case you weren't aware Comcast's TV programming is available anywhere online to TV subscribers. If you are at home it will recognize the modem and log you in automatically. If it's non Comcast connected modem you need to login using your account credentials.
https://www.xfinity.com/stream/
Now to the point, if you have internet only through Comcast some programming is available. Typically it only has crap available however the free previews for things like HBO will be available. From the 11th to the 17th, there will be huge selection from many major premium providers.