First of all this can save you $15 to 30 a month depending on how many TV's you have, but media pc's aren't free either, so you need to determine if the long term cost is worth your wallet.
Below is a picture of the retail box for the HD HomeRun Prime. I think I payed about $200 for my first one, then I got the 2nd one on-sale for $130.
I have Time Warner Cable. They are a bunch of bitches and encrypt everything but the broadcast channels, I am forced to use Windows Media Center. Other cool options if it wasn't for my crappy cable company would have been to use MythTV. Below is a picture of my two HD HomeRun Prime's and the two tuning adapaters. This setup costs less than $3 bucks a month per HD HomeRun. I have 6 network tuners to record and watch TV with.
This is a video of my setup. Two Media PC's and one XBOX enjoying the power of cable TV through the HD HomeRun Prime. Sorry for the crappy video, I took it on my iPhone 4S: But Enjoy Anyway.