The Roku is just used for playback of recorded HD. You basically need a recording device to record OTA HD if that is available to you and lots of storage. For OTA HD you can use a computer card such as the MyHD 120. For recording via satellite to hard drive you can have a satellite receiver modified by nextcom. For more information on this see
www.r5000.com. Works great. For storage you can use something like a buffalo terastion, infrant x6, or a large external USB drive. This would give you lots of storage. Once those kinds of things are in place you simply use the roku for playback from your storage device. One thing to note is the MyHD PC card also does a very good job at playback but I find the roku easier to use. Hopefully this is helpful.
Darin