It's not possible. You would need to have D* integrated into the PC to be able to do it, and there is currently no product out to do that. That will change later this year though, D* and MS are getting together on a box which will integrate D* into Windows Media Center.
I can't envision any way of ever being able to do it on a Mac Mini.
And note that I am NOT criticizing Mac Mini's, or whatever in any way, I'm just saying that the odds of you ever being able to do what you want to do on that computer are very small.