I just came across this very cool multiplatform open source software that allows you to watch free TV by interfacing your popular devices with online streaming sites from an onscreen video on demand style menu:
XBMC is amazing. Can be used on almost any OS Platform including Windows, Mac OS, Linux, and even Android. It's a little tricky to grasp the first time using it. Especially when installing XBMC Addons but after a few short minutes it's really easy. I'd say the only issue you need to overcome would be learning to make sure you're always cautious when downloading or reading instructions because many of the sites out there are so littered with advertisements that sometimes it's almost impossible to see where the site you're on ends and where the ads begin. Finding a site about XBMC and Addons/Plugins that's informative and ad-free is sometimes a bit tough. N2News is great for this reason. No advertisements and strictly a community website so it makes life much easier. They have many different blogs, guides, downloads, and support forums for XBMC, XBMC Addons, and even some information about the old school, "FTA receivers" on the market still.