Wiring up my house was awesome! Every room [except the bathroom...] has cat5, telephone, video from my security cameras, motion sensors, video from the cable company [I don't have cable but i might one day] and audio from my control room so you can hear what I'm working on from any room in the house. It's connected to various amplifiers and in some rooms just the television has a a/v input running the audio only. The recording studio portion of my house also has extra cat5 connections for a headphone monitoring system I plan to buy, regular headphone jacks, 30 mic inputs and 2 outputs, VGA and USB so that I can work from any room by myself with a screen and mouse, and I have a small equipment room that houses my computer and runs everything that needs into my control room [firewire, usb, 1/8 TRS audio, VGA, HDMI, extra cat 5 just in case, and a wire I just ran and attached inside the wall in both rooms for pulling cables in the future should the need arise].
Also, I wired a pair of 20 amp circuits outside for when I get my shop put together, and 20 more amps for lighting and yard power. And then a 65amp circuit for the future hot tub. Yeah, I like to dream. And be prepared.