A couple of days ago I received an invitation to Joost, which is a service that allows you to watch TV via the internet. Here's a Quicktime video that tells you a little bit about it:screenshots.
What makes it different from regular cable or broadcast TV is that the shows aren't scheduled. So, with Joost you can watch a certain show (or episode from a show) whenever you want. It's pretty cool, but when I want to just chill in front of the TV and I don't really care what's on, it's a hassle to skip through the shows and episodes until I find one I haven't seen already. But, it is still in beta testing, so hopefully that can still be fixed somehow (maybe by separating the shows you've already seen from the one's you haven't seen yet).
Besides that, I can dig it. The interface is pretty cool, there's a good selection of channels (with more to be added soon), and there's widgets you can use while your watching TV, such as a news ticker, a widget that reports the weather, a chat box you can use to talk to other people who are viewing the same show, and a few others I don't recall. The website basically tells you everything you need to know, so make sure you check that out.
The service is free, but you can't join right now without an invitation (it's in beta testing mode). I have invitations to give away, so if anyone wants one just leave a comment or send me an email. Make sure you give me your name and your email address or I can't send you the invitation. You should also know that, just like with regular TV, there are at least two channels that are not good for Christians to watch. They are not pornographic per se, but they have sexual content (like Spike TV late at night, or MTV during Spring Break). So, you have to use the same discretion in using Joost that you have to use when deciding to buy (and watch) a regular TV.