For various reasons, I decided I wanted to see about getting some Ethernet wires around the house. I use AirPort Extreme to connect the music room, stereo closet, and server closet (and the laptops), which works fine, but it lacks some things that 100base-T can give me (waking computers, faster transfers, etc.).
The big thing was the stereo closet, where I am streaming movies and audio a lot, and I might be adding another audio player, which would only burden the network further. My stereo closet happens to be below the server closet
My house was built with Leviton home networking something or other systems. Basically, there's cat-5 and coax going to each room in the house (four bedrooms, living room, kitchen, garage), with the coax carrying either satellite or cable (depending on which it is plugged into in the wiring box), and it all connects in one box. The cat-5 is used only for phone, so I have two free pairs to use (actually, I could use three pairs since I only use one for phone, but I need only two for Ethernet, and I might always add a second phone line, though I doubt it).
So I finally got around to rewiring the wiring closet for Ethernet. I bought a little 6-port punchdown module for $25, that converts the four little wires into RJ-45 plugs, and in the rooms I replaced the faceplates with ones that have data, phone, and coax ports (I need to get the coax pieces later, they just pop in, but they were not in stock).
I just need to finish up the faceplates and put a switch in the wiring closet, and I'll be groovy. Right now, it just has two rooms connected directly. There's no power in there, but there's an outlet nearby, I guess I will have to line the cord along the wall.
Although, I did find out that the master bedroom is fed off the living room, and the garage off the kitchen, so only one or the other of those can have Ethernet (unless I add more switches at those locations
Oh, and I made some of my own Ethernet cable. Man, that's a pain in the butt. But cheaper in the long run. Since my walls have only four wires for Ethernet, I saved some pain by using only four wires in my cables, too.