you would use it for normal PC tasks & then for anything multimedia that you can imagine. use it like a TIVO with a good mpeg capture card (hauppauge pvr150 is good). use it to back up dvds, even edit the dvds for content with a good video editing program (pinacle or vegas or something). a decent dvd reader/writer drive isn't too expensive. use it to play dvds that you've stored on your hard-drive (probably a massive RAID array would be ideal). use it to show slide shows & movie clips from the internet on your home theater system. basically... merge your entertainment unit with your computer, I'm doing it : )
What are the capabilities of such a beast? Why invest in one of these? I'm thinking about purchasing a DVD recorder with a built-in hard drive but I also spend A LOT of time on my PC (web surfing, e-mail, accessing company servers from home, etc.) and I'm thinking an HTPC might be a better way to go.
Here's my current set-up:
Westinghouse LTV-32w1 32" LCD
Yamaha HTR 5750
Yamaha NS-BP4500 Home Theater Speakers
Dish Network HD/DVR 942
Samsung HD850 DVD
Microsoft X-Box
Pros and cons of going with an HTPC anyone? Thanks in advance for any input.

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