I have a 3Ghz P4 computer with a 320G HD rigged up in my entertainment system - although I have yet to get a tv card yet to make it into a PVR - (on my to do list).
I have it rigged via wireless to the 'net and can stream stuff to other rooms via a video sender unit which I then plug the reciever into the TV I wish to use (either my bedroom or the spare bedroom). This reciever also can send back infra-red signals back to the computer for basic feature adjustment or I can take the bluetooth mouse and keyboard to each room and controll it - the main system is in a room central for the whole house.
It has been cheap so far as most of the stuff has been donated by friends except for the hard drive. I am using windows media centre but I think I will just stick with standard windows. The motherboard has optical audio out so it is an easy hook up to my system.
I have it rigged via wireless to the 'net and can stream stuff to other rooms via a video sender unit which I then plug the reciever into the TV I wish to use (either my bedroom or the spare bedroom). This reciever also can send back infra-red signals back to the computer for basic feature adjustment or I can take the bluetooth mouse and keyboard to each room and controll it - the main system is in a room central for the whole house.
It has been cheap so far as most of the stuff has been donated by friends except for the hard drive. I am using windows media centre but I think I will just stick with standard windows. The motherboard has optical audio out so it is an easy hook up to my system.



http://www.parker1.co.uk/mythtv_ubuntu.php
Sounds like a good alternative to buying a ready made system, I know there's plenty of other free options out there for Windows too, although many of them seem to be too early in development or have other problems.
So has anyone built their own PVR or Media Centre? If you have, how does it work? Do you have a central server with terminal next to each TV sharing the recordings? Or just one device?