What is needed on the PC side to get the phone jack networking to work?

A 3Com HPNA card, similar to an ethernet card. If you locate the product at Dell's web site, they offer a bundle where they sell you the receiver and the card together.

Alternatively, if your house is already wired for ethernet, you can use that instead.

I know the software was designed by Empeg, but is there any crossover that would benefit Empeg owners? Database compatibility? Similar Interface, searching, etc.?

I'll bet it has the same UI. What I'd like to see is the Receiver automatically find a connected Empeg (even if it's plugged into the host PC via USB) and pull its database and stream the songs from it. That would rock. I don't know if it'll do that or not, but wouldn't that be cool?

Again with the phone line... Are there any technical limitations? Distance from outlet interference? Number of simultaneous connections?

I dunno. Poke around 3Com's site and see what you can come up with.

What sort of performance hit, if any, will be noticed on the serving PC side?

My guess would be that it'd be minimal. Don't try doing anything timing-critical (like competing in a Quake tournament), but I'd say that you could probably get away with just about anything else since the data stream would be just a trickle for most modern PC's. This is just a guess, though, I have no experience with it.

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Tony Fabris