Shotgun:
Finally someone with needs akin to my own! Anyhow, though limited, I'll share my experiences with you.
My MP3 server/jukebox consists of a 7500 A/V (nice and flat for placement in our entertainment center) with 128Mb RAM, G3 400, 12x CD ROM, stock 1Gb HDD, USB card. Obviously, I have yet to upgrade the hard drive, but MP3 CDs serve as a liveable alternative for now.
Other than installing 9.1 and iTunes 2.x I really haven't explored many options in terms of software. But I have given some thought to hardware solutions. Even though I haven't purchased the parts, here's what I'm thinking:
Networking: 802.11g is out and might be a decent, if pricey, option for building a fast network. However, we do own the house we live in, so a wired network may be doable...it just depends on how I feel about punching holes in the walls
Control: It would be great to relocate the computer...even though it fits in the ent center, it's inconvenient to use (the keyboard and trackball must come out for each use then stowed away). Additionally, since the computer is easy to get at, it's easy to shut down. It would be great to leave it running and keep the tunes flowing! In this case, controlling the machine from a remote location becomes the issue. For me, Timbuktu is not an option because the goal is to get away from using the jukebox as a computer. I'd like to control everything from my couch not another computer!
So, RF keyboard and mouse? Maybe, but distance may be an issue. IR extender coupled with a USB remote (Keyspan?)? Maybe (haven't researched this one yet). Some kind of "long-range" wired solution? Dunno.
Viewing: In order to display the jukebox's screen I'm using an Apple Presentation System. It hooks up to the computer's VGA port, converts the video to NTSC, and sends the data to a TV via RCA or S-Video. Nice device for $20! However, I'm going to have to perform some serious juju in order to send a video signal over 100+ feet of cable with minimal degredation. Or is there a better way? Wireless (sounds spendy)?
As for building a remote, I have no clue...though that would certainly be interesting!
I know I didn't really answer your questions (as I have a lot of the same), but if you'd like to collaborate on this let me know. I'd jump at the chance to bounce some ideas off someone with similar interests!
email: gripley at thecreek dot com
Cheers!