i had one on my last computer. The cable went from my wall directly in to my video card. But you still need to pay your cable bill to get the channels. It's not free.

I only had it because i didnt own a TV in college so I used my PC as one.

I think some tv tuners have an antenna function so u could get basic broadcast channels, though.

ATI makes good video cards with TV Tuners. Probably the best.

I haven't got one, but a co-worker raves about this. Getting it configured is no easy task though.
www.mythtv.org/

I have a TV tuner card in my computer .. and have had it for the last 2-3 years now. I don't know how I lived without it before.

I bought it when all of my friends were out buying themselves nice things. I got tired of feeling left out, so I splurged, too. While they bought motorcycles, dirt bikes, Corvettes and the like, I dropped $30 or so (including shipping) on my tuner card. My G/F liked it so much, she made me buy one for her, too.

Installing it is just like installing any other card (for a PC, anyway ... I've never experienced a Mac). Setup is easy, too ... it virtually does everything for you. At least mine did. When it's installed and configured, you should be able to watch any channel your antenna or cable/satellite system can pick up. In the case of a satellite system, you may need a "set top" box and tune your tuner card to channel 3 or 4 (like any other tv), but it should work.

Once that's done, you can watch all your favorite shows on your computer screen. My card will allow resizing of the screen from smaller than a postage stamp to full screen. I currently have a 20" monitor. I have also learned to "record" my favorite shows (just like a VCR, but uses hard drive space instead) and then use Microsoft Movie Maker (free from www.microsoft.com) to edit the commercials out.

For $30 or so, it's the cheapest tv you can ever buy and it'll allow you to sit in front of your computer to keep working or do other things. Of course, there are more expensive tuners out there that come with remotes and things that mine didn't, but all that means is there is a card for virtually every budget.